51391955 has 16 divisors (see below), whose sum is σ = 64171008. Its totient is φ = 39468000.

The previous prime is 51391937. The next prime is 51392027. The reversal of 51391955 is 55919315.

It is not a de Polignac number, because 51391955 - 2⁸ = 51391699 is a prime.

It is a super-2 number, since 2×51391955² = 5282266077444050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19040 + ... + 21570.

It is an arithmetic number, because the mean of its divisors is an integer number (4010688).

Almost surely, 2^51391955 is an apocalyptic number.

51391955 is a deficient number, since it is larger than the sum of its proper divisors (12779053).

51391955 is a wasteful number, since it uses less digits than its factorization.

51391955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2698.

The product of its digits is 30375, while the sum is 38.

The square root of 51391955 is about 7168.8182429184. The cubic root of 51391955 is about 371.7905780634.

The spelling of 51391955 in words is "fifty-one million, three hundred ninety-one thousand, nine hundred fifty-five".