21251350452 has 24 divisors (see below), whose sum is σ = 51296364000. Its totient is φ = 6839514976.

The previous prime is 21251350447. The next prime is 21251350499. The reversal of 21251350452 is 25405315212.

It is a congruent number.

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, 30533202 + ... + 30533897.

It is an arithmetic number, because the mean of its divisors is an integer number (2137348500).

Almost surely, 2^21251350452 is an apocalyptic number.

It is an amenable number.

21251350452 is an abundant number, since it is smaller than the sum of its proper divisors (30045013548).

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

21251350452 is a wasteful number, since it uses less digits than its factorization.

21251350452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61067135 (or 61067133 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

Adding to 21251350452 its reverse (25405315212), we get a palindrome (46656665664).

The spelling of 21251350452 in words is "twenty-one billion, two hundred fifty-one million, three hundred fifty thousand, four hundred fifty-two".