291126631 has 2 divisors, whose sum is σ = 291126632. Its totient is φ = 291126630.

The previous prime is 291126599. The next prime is 291126637. The reversal of 291126631 is 136621192.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 291126631 - 2⁵ = 291126599 is a prime.

It is a super-2 number, since 2×291126631² = 169509430554820322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 291126593 and 291126602.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (291126637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145563315 + 145563316.

It is an arithmetic number, because the mean of its divisors is an integer number (145563316).

Almost surely, 2^291126631 is an apocalyptic number.

291126631 is a deficient number, since it is larger than the sum of its proper divisors (1).

291126631 is an equidigital number, since it uses as much as digits as its factorization.

291126631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 31.

The square root of 291126631 is about 17062.4333258771. The cubic root of 291126631 is about 662.7666469537.

The spelling of 291126631 in words is "two hundred ninety-one million, one hundred twenty-six thousand, six hundred thirty-one".