51523615 has 24 divisors (see below), whose sum is σ = 73198944. Its totient is φ = 34584000.

The previous prime is 51523553. The next prime is 51523621. The reversal of 51523615 is 51632515.

It is not a de Polignac number, because 51523615 - 2¹⁷ = 51392543 is a prime.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4590 + ... + 11140.

It is an arithmetic number, because the mean of its divisors is an integer number (3049956).

Almost surely, 2^51523615 is an apocalyptic number.

51523615 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51523615 is a deficient number, since it is larger than the sum of its proper divisors (21675329).

51523615 is a wasteful number, since it uses less digits than its factorization.

51523615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6591 (or 6580 counting only the distinct ones).

The product of its digits is 4500, while the sum is 28.

The square root of 51523615 is about 7177.9951936456. The cubic root of 51523615 is about 372.1078015510.

Subtracting 51523615 from its reverse (51632515), we obtain a square (108900 = 330²).

The spelling of 51523615 in words is "fifty-one million, five hundred twenty-three thousand, six hundred fifteen".