816631919 has 2 divisors, whose sum is σ = 816631920. Its totient is φ = 816631918.

The previous prime is 816631883. The next prime is 816631943. The reversal of 816631919 is 919136618.

It is a happy number.

816631919 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 816631919 - 2⁸ = 816631663 is a prime.

It is a super-2 number, since 2×816631919² = 1333775382259245122, 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 816631919.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (816631019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 408315959 + 408315960.

It is an arithmetic number, because the mean of its divisors is an integer number (408315960).

Almost surely, 2^816631919 is an apocalyptic number.

816631919 is a deficient number, since it is larger than the sum of its proper divisors (1).

816631919 is an equidigital number, since it uses as much as digits as its factorization.

816631919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69984, while the sum is 44.

The square root of 816631919 is about 28576.7723684814. The cubic root of 816631919 is about 934.7069034707.

The spelling of 816631919 in words is "eight hundred sixteen million, six hundred thirty-one thousand, nine hundred nineteen".