51520415554 has 4 divisors (see below), whose sum is σ = 77280623334. Its totient is φ = 25760207776.

The previous prime is 51520415539. The next prime is 51520415579. The reversal of 51520415554 is 45551402515.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 26737155225 + 24783260329 = 163515^2 + 157427^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12880103887 + ... + 12880103890.

Almost surely, 2^51520415554 is an apocalyptic number.

51520415554 is a deficient number, since it is larger than the sum of its proper divisors (25760207780).

51520415554 is a wasteful number, since it uses less digits than its factorization.

51520415554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25760207779.

The product of its (nonzero) digits is 100000, while the sum is 37.

The spelling of 51520415554 in words is "fifty-one billion, five hundred twenty million, four hundred fifteen thousand, five hundred fifty-four".