51865387 has 16 divisors (see below), whose sum is σ = 61437952. Its totient is φ = 42845760.

The previous prime is 51865343. The next prime is 51865397. The reversal of 51865387 is 78356815.

It is a cyclic number.

It is not a de Polignac number, because 51865387 - 2¹⁹ = 51341099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51865397) 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, 98908 + ... + 99430.

It is an arithmetic number, because the mean of its divisors is an integer number (3839872).

Almost surely, 2^51865387 is an apocalyptic number.

51865387 is a deficient number, since it is larger than the sum of its proper divisors (9572565).

51865387 is a wasteful number, since it uses less digits than its factorization.

51865387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018.

The product of its digits is 201600, while the sum is 43.

The square root of 51865387 is about 7201.7627703223. The cubic root of 51865387 is about 372.9287575341.

The spelling of 51865387 in words is "fifty-one million, eight hundred sixty-five thousand, three hundred eighty-seven".