21252452616 has 48 divisors (see below), whose sum is σ = 58644750060. Its totient is φ = 6950486400.

The previous prime is 21252452593. The next prime is 21252452647. The reversal of 21252452616 is 61625425212.

21252452616 is a `hidden beast` number, since 2 + 12 + 5 + 24 + 5 + 2 + 616 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 20579050116 + 673402500 = 143454^2 + 25950^2 .

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

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 2780835 + ... + 2788466.

Almost surely, 2^21252452616 is an apocalyptic number.

It is an amenable number.

21252452616 is an abundant number, since it is smaller than the sum of its proper divisors (37392297444).

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

21252452616 is a wasteful number, since it uses less digits than its factorization.

21252452616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5569366 (or 5569359 counting only the distinct ones).

The product of its digits is 57600, while the sum is 36.

Adding to 21252452616 its reverse (61625425212), we get a palindrome (82877877828).

The spelling of 21252452616 in words is "twenty-one billion, two hundred fifty-two million, four hundred fifty-two thousand, six hundred sixteen".