216117631 has 2 divisors, whose sum is σ = 216117632. Its totient is φ = 216117630.

The previous prime is 216117611. The next prime is 216117653. The reversal of 216117631 is 136711612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 216117631 - 2¹¹ = 216115583 is a prime.

It is a super-2 number, since 2×216117631² = 93413660858104322, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 216117631.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216117611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108058815 + 108058816.

It is an arithmetic number, because the mean of its divisors is an integer number (108058816).

Almost surely, 2^216117631 is an apocalyptic number.

216117631 is a deficient number, since it is larger than the sum of its proper divisors (1).

216117631 is an equidigital number, since it uses as much as digits as its factorization.

216117631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1512, while the sum is 28.

The square root of 216117631 is about 14700.9397998903. The cubic root of 216117631 is about 600.1088978268.

The spelling of 216117631 in words is "two hundred sixteen million, one hundred seventeen thousand, six hundred thirty-one".