51015121556 has 24 divisors (see below), whose sum is σ = 102070570560. Its totient is φ = 21854981952.

The previous prime is 51015121471. The next prime is 51015121561. The reversal of 51015121556 is 65512151015.

It is a super-2 number, since 2×51015121556² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 287705 + ... + 429888.

It is an arithmetic number, because the mean of its divisors is an integer number (4252940440).

Almost surely, 2^51015121556 is an apocalyptic number.

It is an amenable number.

51015121556 is an abundant number, since it is smaller than the sum of its proper divisors (51055449004).

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

51015121556 is a wasteful number, since it uses less digits than its factorization.

51015121556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 720143 (or 720141 counting only the distinct ones).

The product of its (nonzero) digits is 7500, while the sum is 32.

The spelling of 51015121556 in words is "fifty-one billion, fifteen million, one hundred twenty-one thousand, five hundred fifty-six".