20642976 has 72 divisors (see below), whose sum is σ = 59148180. Its totient is φ = 6829056.

The previous prime is 20642971. The next prime is 20643043. The reversal of 20642976 is 67924602.

It is a happy number.

20642976 is a `hidden beast` number, since 2 + 0 + 642 + 9 + 7 + 6 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 20466576 + 176400 = 4524^2 + 420^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×20642976² = 852264916273152, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 20642976.

It is not an unprimeable number, because it can be changed into a prime (20642971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65796 + ... + 66108.

Almost surely, 2^20642976 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20642976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29574090).

20642976 is an abundant number, since it is smaller than the sum of its proper divisors (38505204).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20642976 is a wasteful number, since it uses less digits than its factorization.

20642976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 558 (or 547 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 20642976 is about 4543.4541925720. The cubic root of 20642976 is about 274.3199771186.

The spelling of 20642976 in words is "twenty million, six hundred forty-two thousand, nine hundred seventy-six".