21504343952 has 40 divisors (see below), whose sum is σ = 51279592896. Its totient is φ = 8507212416.

The previous prime is 21504343937. The next prime is 21504343957. The reversal of 21504343952 is 25934340512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21504343957) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7383278 + ... + 7386189.

Almost surely, 2^21504343952 is an apocalyptic number.

It is an amenable number.

21504343952 is an abundant number, since it is smaller than the sum of its proper divisors (29775248944).

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

21504343952 is a wasteful number, since it uses less digits than its factorization.

21504343952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14769495 (or 14769489 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 38.

The spelling of 21504343952 in words is "twenty-one billion, five hundred four million, three hundred forty-three thousand, nine hundred fifty-two".