21390575088 has 20 divisors (see below), whose sum is σ = 55258985768. Its totient is φ = 7130191680.

The previous prime is 21390575077. The next prime is 21390575099. The reversal of 21390575088 is 88057509312.

It is an interprime number because it is at equal distance from previous prime (21390575077) and next prime (21390575099).

It is a Harshad number since it is a multiple of its sum of digits (48), and also a Moran number because the ratio is a prime number: 445636981 = 21390575088 / (2 + 1 + 3 + 9 + 0 + 5 + 7 + 5 + 0 + 8 + 8).

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, 222818443 + ... + 222818538.

Almost surely, 2^21390575088 is an apocalyptic number.

It is an amenable number.

21390575088 is an abundant number, since it is smaller than the sum of its proper divisors (33868410680).

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

21390575088 is a wasteful number, since it uses less digits than its factorization.

21390575088 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 445636992 (or 445636986 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 48.

The spelling of 21390575088 in words is "twenty-one billion, three hundred ninety million, five hundred seventy-five thousand, eighty-eight".