51644615 has 12 divisors (see below), whose sum is σ = 68120472. Its totient is φ = 37559280.

The previous prime is 51644597. The next prime is 51644617.

51644615 is nontrivially palindromic in base 10.

It is a de Polignac number, because none of the positive numbers 2^k-51644615 is a prime.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51644617) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42077 + ... + 43286.

It is an arithmetic number, because the mean of its divisors is an integer number (5676706).

Almost surely, 2^51644615 is an apocalyptic number.

51644615 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51644615 is a deficient number, since it is larger than the sum of its proper divisors (16475857).

51644615 is a wasteful number, since it uses less digits than its factorization.

51644615 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85390 (or 85379 counting only the distinct ones).

The product of its digits is 14400, while the sum is 32.

The square root of 51644615 is about 7186.4187882422. The cubic root of 51644615 is about 372.3988644855.

It can be divided in two parts, 5164 and 4615, that added together give a palindrome (9779).

The spelling of 51644615 in words is "fifty-one million, six hundred forty-four thousand, six hundred fifteen".