128402694631 has 2 divisors, whose sum is σ = 128402694632. Its totient is φ = 128402694630.

The previous prime is 128402694593. The next prime is 128402694649. The reversal of 128402694631 is 136496204821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128402694631 - 2¹³ = 128402686439 is a prime.

It is a super-2 number, since 2×128402694631² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128402694661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64201347315 + 64201347316.

It is an arithmetic number, because the mean of its divisors is an integer number (64201347316).

Almost surely, 2^128402694631 is an apocalyptic number.

128402694631 is a deficient number, since it is larger than the sum of its proper divisors (1).

128402694631 is an equidigital number, since it uses as much as digits as its factorization.

128402694631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 497664, while the sum is 46.

The spelling of 128402694631 in words is "one hundred twenty-eight billion, four hundred two million, six hundred ninety-four thousand, six hundred thirty-one".