216903131 has 2 divisors, whose sum is σ = 216903132. Its totient is φ = 216903130.

The previous prime is 216903109. The next prime is 216903149. The reversal of 216903131 is 131309612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 216903131 - 2⁶ = 216903067 is a prime.

It is a super-2 number, since 2×216903131² = 94093936475206322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 216903131.

It is not a weakly prime, because it can be changed into another prime (216903191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108451565 + 108451566.

It is an arithmetic number, because the mean of its divisors is an integer number (108451566).

Almost surely, 2^216903131 is an apocalyptic number.

216903131 is a deficient number, since it is larger than the sum of its proper divisors (1).

216903131 is an equidigital number, since it uses as much as digits as its factorization.

216903131 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 216903131 is about 14727.6315475368. The cubic root of 216903131 is about 600.8350696327.

The spelling of 216903131 in words is "two hundred sixteen million, nine hundred three thousand, one hundred thirty-one".