216351431 has 2 divisors, whose sum is σ = 216351432. Its totient is φ = 216351430.

The previous prime is 216351403. The next prime is 216351491. The reversal of 216351431 is 134153612.

216351431 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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216351431 is a prime.

It is a super-2 number, since 2×216351431² = 93615883391495522, 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 216351431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216351491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108175715 + 108175716.

It is an arithmetic number, because the mean of its divisors is an integer number (108175716).

Almost surely, 2^216351431 is an apocalyptic number.

216351431 is a deficient number, since it is larger than the sum of its proper divisors (1).

216351431 is an equidigital number, since it uses as much as digits as its factorization.

216351431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 26.

The square root of 216351431 is about 14708.8895230061. The cubic root of 216351431 is about 600.3252227592.

The spelling of 216351431 in words is "two hundred sixteen million, three hundred fifty-one thousand, four hundred thirty-one".