51172857 has 16 divisors (see below), whose sum is σ = 76524480. Its totient is φ = 33794496.

The previous prime is 51172829. The next prime is 51172897. The reversal of 51172857 is 75827115.

It is not a de Polignac number, because 51172857 - 2⁷ = 51172729 is a prime.

It is a super-2 number, since 2×51172857² = 5237322587084898, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (51172817) 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, 5968 + ... + 11745.

It is an arithmetic number, because the mean of its divisors is an integer number (4782780).

Almost surely, 2^51172857 is an apocalyptic number.

It is an amenable number.

51172857 is a deficient number, since it is larger than the sum of its proper divisors (25351623).

51172857 is a wasteful number, since it uses less digits than its factorization.

51172857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17829 (or 17823 counting only the distinct ones).

The product of its digits is 19600, while the sum is 36.

The square root of 51172857 is about 7153.5206017736. The cubic root of 51172857 is about 371.2614770455.

The spelling of 51172857 in words is "fifty-one million, one hundred seventy-two thousand, eight hundred fifty-seven".