816626537 has 2 divisors, whose sum is σ = 816626538. Its totient is φ = 816626536.

The previous prime is 816626513. The next prime is 816626543. The reversal of 816626537 is 735626618.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 786858601 + 29767936 = 28051^2 + 5456^2 .

It is a cyclic number.

It is not a de Polignac number, because 816626537 - 2⁸ = 816626281 is a prime.

It is a super-2 number, since 2×816626537² = 1333757801865224738, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (816626507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 408313268 + 408313269.

It is an arithmetic number, because the mean of its divisors is an integer number (408313269).

Almost surely, 2^816626537 is an apocalyptic number.

It is an amenable number.

816626537 is a deficient number, since it is larger than the sum of its proper divisors (1).

816626537 is an equidigital number, since it uses as much as digits as its factorization.

816626537 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 44.

The square root of 816626537 is about 28576.6782009386. The cubic root of 816626537 is about 934.7048500757.

The spelling of 816626537 in words is "eight hundred sixteen million, six hundred twenty-six thousand, five hundred thirty-seven".