216443431 has 2 divisors, whose sum is σ = 216443432. Its totient is φ = 216443430.

The previous prime is 216443417. The next prime is 216443449. The reversal of 216443431 is 134344612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 216443431 - 2²⁵ = 182888999 is a prime.

It is a super-2 number, since 2×216443431² = 93695517646103522, 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 216443431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216443401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108221715 + 108221716.

It is an arithmetic number, because the mean of its divisors is an integer number (108221716).

Almost surely, 2^216443431 is an apocalyptic number.

216443431 is a deficient number, since it is larger than the sum of its proper divisors (1).

216443431 is an equidigital number, since it uses as much as digits as its factorization.

216443431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 28.

The square root of 216443431 is about 14712.0165511054. The cubic root of 216443431 is about 600.4103036135.

The spelling of 216443431 in words is "two hundred sixteen million, four hundred forty-three thousand, four hundred thirty-one".