21572000825 has 48 divisors (see below), whose sum is σ = 28646510256. Its totient is φ = 16057958400.

The previous prime is 21572000767. The next prime is 21572000837. The reversal of 21572000825 is 52800027512.

It is a happy number.

It can be written as a sum of positive squares in 24 ways, for example, as 14091826681 + 7480174144 = 118709^2 + 86488^2 .

It is not a de Polignac number, because 21572000825 - 2⁶ = 21572000761 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21572000791 and 21572000800.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 14845799 + ... + 14847251.

It is an arithmetic number, because the mean of its divisors is an integer number (596802297).

Almost surely, 2^21572000825 is an apocalyptic number.

21572000825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21572000825 is a deficient number, since it is larger than the sum of its proper divisors (7074509431).

21572000825 is a wasteful number, since it uses less digits than its factorization.

21572000825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1854 (or 1849 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 32.

The spelling of 21572000825 in words is "twenty-one billion, five hundred seventy-two million, eight hundred twenty-five", and thus it is an aban number.