20642970 has 32 divisors (see below), whose sum is σ = 50481792. Its totient is φ = 5400512.

The previous prime is 20642903. The next prime is 20642971. The reversal of 20642970 is 7924602.

It is a happy number.

It is a super-2 number, since 2×20642970² = 852264420841800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a Curzon number.

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

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4902 + ... + 8081.

It is an arithmetic number, because the mean of its divisors is an integer number (1577556).

Almost surely, 2^20642970 is an apocalyptic number.

20642970 is an abundant number, since it is smaller than the sum of its proper divisors (29838822).

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

20642970 is a wasteful number, since it uses less digits than its factorization.

20642970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13046.

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 20642970 is about 4543.4535322814. The cubic root of 20642970 is about 274.3199505411.

It can be divided in two parts, 20642 and 970, that added together give a palindrome (21612).

The spelling of 20642970 in words is "twenty million, six hundred forty-two thousand, nine hundred seventy".