51215510690 has 16 divisors (see below), whose sum is σ = 92190708792. Its totient is φ = 20485584384.

The previous prime is 51215510623. The next prime is 51215510693. The reversal of 51215510690 is 9601551215.

It can be written as a sum of positive squares in 4 ways, for example, as 27419054569 + 23796456121 = 165587^2 + 154261^2 .

It is a super-2 number, since 2×51215510690² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51215510690.

It is not an unprimeable number, because it can be changed into a prime (51215510693) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 424172 + ... + 531368.

Almost surely, 2^51215510690 is an apocalyptic number.

51215510690 is a deficient number, since it is larger than the sum of its proper divisors (40975198102).

51215510690 is a wasteful number, since it uses less digits than its factorization.

51215510690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154981.

The product of its (nonzero) digits is 13500, while the sum is 35.

The spelling of 51215510690 in words is "fifty-one billion, two hundred fifteen million, five hundred ten thousand, six hundred ninety".