21265968528 has 80 divisors (see below), whose sum is σ = 69761388160. Its totient is φ = 6075990144.

The previous prime is 21265968527. The next prime is 21265968539. The reversal of 21265968528 is 82586956212.

21265968528 is a `hidden beast` number, since 2 + 1 + 2 + 6 + 59 + 68 + 528 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (21265968523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3513175 + ... + 3519222.

It is an arithmetic number, because the mean of its divisors is an integer number (872017352).

Almost surely, 2^21265968528 is an apocalyptic number.

21265968528 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21265968528 is an abundant number, since it is smaller than the sum of its proper divisors (48495419632).

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

21265968528 is a wasteful number, since it uses less digits than its factorization.

21265968528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7032421 (or 7032409 counting only the distinct ones).

The product of its digits is 4147200, while the sum is 54.

The spelling of 21265968528 in words is "twenty-one billion, two hundred sixty-five million, nine hundred sixty-eight thousand, five hundred twenty-eight".