21233052640 has 24 divisors (see below), whose sum is σ = 50163087240. Its totient is φ = 8493220992.

The previous prime is 21233052563. The next prime is 21233052671. The reversal of 21233052640 is 4625033212.

It is a junction number, because it is equal to n+sod(n) for n = 21233052599 and 21233052608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66353130 + ... + 66353449.

It is an arithmetic number, because the mean of its divisors is an integer number (2090128635).

Almost surely, 2^21233052640 is an apocalyptic number.

21233052640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21233052640 is an abundant number, since it is smaller than the sum of its proper divisors (28930034600).

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

21233052640 is a wasteful number, since it uses less digits than its factorization.

21233052640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132706594 (or 132706586 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 28.

Adding to 21233052640 its reverse (4625033212), we get a palindrome (25858085852).

The spelling of 21233052640 in words is "twenty-one billion, two hundred thirty-three million, fifty-two thousand, six hundred forty".