51556615 has 16 divisors (see below), whose sum is σ = 68422176. Its totient is φ = 36979200.

The previous prime is 51556607. The next prime is 51556621. The reversal of 51556615 is 51665515.

It is not a de Polignac number, because 51556615 - 2³ = 51556607 is a prime.

It is a Duffinian number.

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 15 ways as a sum of consecutive naturals, for example, 2406 + ... + 10435.

It is an arithmetic number, because the mean of its divisors is an integer number (4276386).

Almost surely, 2^51556615 is an apocalyptic number.

51556615 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51556615 is a deficient number, since it is larger than the sum of its proper divisors (16865561).

51556615 is a wasteful number, since it uses less digits than its factorization.

51556615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12930.

The product of its digits is 22500, while the sum is 34.

The square root of 51556615 is about 7180.2935176774. The cubic root of 51556615 is about 372.1872275047.

Subtracting 51556615 from its reverse (51665515), we obtain a square (108900 = 330²).

The spelling of 51556615 in words is "fifty-one million, five hundred fifty-six thousand, six hundred fifteen".