21064625418 has 16 divisors (see below), whose sum is σ = 42130833120. Its totient is φ = 7021278096.

The previous prime is 21064625399. The next prime is 21064625419. The reversal of 21064625418 is 81452646012.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21064625419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 174696 + ... + 269532.

It is an arithmetic number, because the mean of its divisors is an integer number (2633177070).

Almost surely, 2^21064625418 is an apocalyptic number.

21064625418 is an abundant number, since it is smaller than the sum of its proper divisors (21066207702).

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

21064625418 is a wasteful number, since it uses less digits than its factorization.

21064625418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131861.

The product of its (nonzero) digits is 92160, while the sum is 39.

The spelling of 21064625418 in words is "twenty-one billion, sixty-four million, six hundred twenty-five thousand, four hundred eighteen".