21235251552 has 48 divisors (see below), whose sum is σ = 55762805952. Its totient is φ = 7075843200.

The previous prime is 21235251509. The next prime is 21235251577. The reversal of 21235251552 is 25515253212.

It is a tau number, because it is divible by the number of its divisors (48).

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, 234903 + ... + 312489.

It is an arithmetic number, because the mean of its divisors is an integer number (1161725124).

Almost surely, 2^21235251552 is an apocalyptic number.

It is an amenable number.

21235251552 is an abundant number, since it is smaller than the sum of its proper divisors (34527554400).

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

21235251552 is a wasteful number, since it uses less digits than its factorization.

21235251552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80451 (or 80443 counting only the distinct ones).

The product of its digits is 30000, while the sum is 33.

The spelling of 21235251552 in words is "twenty-one billion, two hundred thirty-five million, two hundred fifty-one thousand, five hundred fifty-two".