51308985 has 32 divisors (see below), whose sum is σ = 101041920. Its totient is φ = 21650688.

The previous prime is 51308963. The next prime is 51308989. The reversal of 51308985 is 58980315.

It is not a de Polignac number, because 51308985 - 2⁵ = 51308953 is a prime.

It is a super-2 number, since 2×51308985² = 5265223883460450, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (51308989) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17430 + ... + 20159.

It is an arithmetic number, because the mean of its divisors is an integer number (3157560).

Almost surely, 2^51308985 is an apocalyptic number.

It is an amenable number.

51308985 is a deficient number, since it is larger than the sum of its proper divisors (49732935).

51308985 is a wasteful number, since it uses less digits than its factorization.

51308985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37617.

The product of its (nonzero) digits is 43200, while the sum is 39.

The square root of 51308985 is about 7163.0290380537. The cubic root of 51308985 is about 371.5903905711.

The spelling of 51308985 in words is "fifty-one million, three hundred eight thousand, nine hundred eighty-five".