51987123641 has 2 divisors, whose sum is σ = 51987123642. Its totient is φ = 51987123640.

The previous prime is 51987123631. The next prime is 51987123691. The reversal of 51987123641 is 14632178915.

51987123641 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29642853241 + 22344270400 = 172171^2 + 149480^2 .

It is a cyclic number.

It is not a de Polignac number, because 51987123641 - 2²⁶ = 51920014777 is a prime.

It is a super-2 number, since 2×51987123641² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51987123631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25993561820 + 25993561821.

It is an arithmetic number, because the mean of its divisors is an integer number (25993561821).

Almost surely, 2^51987123641 is an apocalyptic number.

It is an amenable number.

51987123641 is a deficient number, since it is larger than the sum of its proper divisors (1).

51987123641 is an equidigital number, since it uses as much as digits as its factorization.

51987123641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 47.

The spelling of 51987123641 in words is "fifty-one billion, nine hundred eighty-seven million, one hundred twenty-three thousand, six hundred forty-one".