51555516 has 24 divisors (see below), whose sum is σ = 120465744. Its totient is φ = 17160960.

The previous prime is 51555499. The next prime is 51555521. The reversal of 51555516 is 61555515.

51555516 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7236 + ... + 12468.

It is an arithmetic number, because the mean of its divisors is an integer number (5019406).

Almost surely, 2^51555516 is an apocalyptic number.

It is an amenable number.

51555516 is an abundant number, since it is smaller than the sum of its proper divisors (68910228).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51555516 is a wasteful number, since it uses less digits than its factorization.

51555516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6061 (or 6059 counting only the distinct ones).

The product of its digits is 18750, while the sum is 33.

The square root of 51555516 is about 7180.2169883646. The cubic root of 51555516 is about 372.1845829254.

Subtracting 51555516 from its reverse (61555515), we obtain a palindrome (9999999).

The spelling of 51555516 in words is "fifty-one million, five hundred fifty-five thousand, five hundred sixteen".