20642760 has 96 divisors (see below), whose sum is σ = 71056440. Its totient is φ = 5179392.

The previous prime is 20642731. The next prime is 20642773. The reversal of 20642760 is 6724602.

It can be written as a sum of positive squares in 4 ways, for example, as 20629764 + 12996 = 4542^2 + 114^2 .

It is a super-2 number, since 2×20642760² = 852247080835200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4434 + ... + 7806.

Almost surely, 2^20642760 is an apocalyptic number.

20642760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20642760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35528220).

20642760 is an abundant number, since it is smaller than the sum of its proper divisors (50413680).

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

20642760 is a wasteful number, since it uses less digits than its factorization.

20642760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3407 (or 3400 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 20642760 is about 4543.4304220490. The cubic root of 20642760 is about 274.3190203231.

The spelling of 20642760 in words is "twenty million, six hundred forty-two thousand, seven hundred sixty".