189918894631 has 2 divisors, whose sum is σ = 189918894632. Its totient is φ = 189918894630.

The previous prime is 189918894623. The next prime is 189918894647. The reversal of 189918894631 is 136498819981.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 189918894631 - 2³ = 189918894623 is a prime.

It is a super-2 number, since 2×189918894631² (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 (189918894331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94959447315 + 94959447316.

It is an arithmetic number, because the mean of its divisors is an integer number (94959447316).

Almost surely, 2^189918894631 is an apocalyptic number.

189918894631 is a deficient number, since it is larger than the sum of its proper divisors (1).

189918894631 is an equidigital number, since it uses as much as digits as its factorization.

189918894631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26873856, while the sum is 67.

The spelling of 189918894631 in words is "one hundred eighty-nine billion, nine hundred eighteen million, eight hundred ninety-four thousand, six hundred thirty-one".