191628631 has 2 divisors, whose sum is σ = 191628632. Its totient is φ = 191628630.

The previous prime is 191628611. The next prime is 191628653. The reversal of 191628631 is 136826191.

191628631 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 is an emirp because it is prime and its reverse (136826191) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 191628631 - 2¹¹ = 191626583 is a prime.

It is a super-2 number, since 2×191628631² = 73443064437868322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191628601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95814315 + 95814316.

It is an arithmetic number, because the mean of its divisors is an integer number (95814316).

Almost surely, 2^191628631 is an apocalyptic number.

191628631 is a deficient number, since it is larger than the sum of its proper divisors (1).

191628631 is an equidigital number, since it uses as much as digits as its factorization.

191628631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 37.

The square root of 191628631 is about 13842.9993498519. Note that the first 3 decimals coincide. The cubic root of 191628631 is about 576.5276389020.

The spelling of 191628631 in words is "one hundred ninety-one million, six hundred twenty-eight thousand, six hundred thirty-one".