21021123432 has 32 divisors (see below), whose sum is σ = 52856592480. Its totient is φ = 6966536640.

The previous prime is 21021123419. The next prime is 21021123443. The reversal of 21021123432 is 23432112012.

It is a junction number, because it is equal to n+sod(n) for n = 21021123399 and 21021123408.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2527294 + ... + 2535597.

It is an arithmetic number, because the mean of its divisors is an integer number (1651768515).

Almost surely, 2^21021123432 is an apocalyptic number.

It is an amenable number.

21021123432 is an abundant number, since it is smaller than the sum of its proper divisors (31835469048).

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

21021123432 is a wasteful number, since it uses less digits than its factorization.

21021123432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5063073 (or 5063069 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21021123432 its reverse (23432112012), we get a palindrome (44453235444).

It can be divided in two parts, 21021 and 123432, that added together give a triangular number (144453 = T₅₃₇).

The spelling of 21021123432 in words is "twenty-one billion, twenty-one million, one hundred twenty-three thousand, four hundred thirty-two".