51535581 has 16 divisors (see below), whose sum is σ = 74827200. Its totient is φ = 31425408.

The previous prime is 51535559. The next prime is 51535607. The reversal of 51535581 is 18553515.

It is not a de Polignac number, because 51535581 - 2¹⁵ = 51502813 is a prime.

It is a super-2 number, since 2×51535581² = 5311832218015122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51535181) 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, 13936 + ... + 17241.

It is an arithmetic number, because the mean of its divisors is an integer number (4676700).

Almost surely, 2^51535581 is an apocalyptic number.

It is an amenable number.

51535581 is a deficient number, since it is larger than the sum of its proper divisors (23291619).

51535581 is a wasteful number, since it uses less digits than its factorization.

51535581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31228.

The product of its digits is 15000, while the sum is 33.

The square root of 51535581 is about 7178.8286649007. The cubic root of 51535581 is about 372.1366058013.

The spelling of 51535581 in words is "fifty-one million, five hundred thirty-five thousand, five hundred eighty-one".