21056259852 has 36 divisors (see below), whose sum is σ = 54594213240. Its totient is φ = 7018250616.

The previous prime is 21056259817. The next prime is 21056259881. The reversal of 21056259852 is 25895265012.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

21056259852 is a `hidden beast` number, since 2 + 1 + 0 + 5 + 6 + 2 + 598 + 52 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a junction number, because it is equal to n+sod(n) for n = 21056259798 and 21056259807.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1501023 + ... + 1514985.

Almost surely, 2^21056259852 is an apocalyptic number.

It is an amenable number.

21056259852 is an abundant number, since it is smaller than the sum of its proper divisors (33537953388).

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

21056259852 is an frugal number, since it uses more digits than its factorization.

21056259852 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27939 (or 13968 counting only the distinct ones).

The product of its (nonzero) digits is 432000, while the sum is 45.

The spelling of 21056259852 in words is "twenty-one billion, fifty-six million, two hundred fifty-nine thousand, eight hundred fifty-two".