20857715125 has 32 divisors (see below), whose sum is σ = 28416941280. Its totient is φ = 15191539200.

The previous prime is 20857715111. The next prime is 20857715141. The reversal of 20857715125 is 52151775802.

It can be written as a sum of positive squares in 16 ways, for example, as 20846161924 + 11553201 = 144382^2 + 3399^2 .

It is not a de Polignac number, because 20857715125 - 2⁵ = 20857715093 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30711 + ... + 206539.

It is an arithmetic number, because the mean of its divisors is an integer number (888029415).

Almost surely, 2^20857715125 is an apocalyptic number.

20857715125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20857715125 is a deficient number, since it is larger than the sum of its proper divisors (7559226155).

20857715125 is a wasteful number, since it uses less digits than its factorization.

20857715125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175930 (or 175920 counting only the distinct ones).

The product of its (nonzero) digits is 196000, while the sum is 43.

The spelling of 20857715125 in words is "twenty billion, eight hundred fifty-seven million, seven hundred fifteen thousand, one hundred twenty-five".