616635997 has 2 divisors, whose sum is σ = 616635998. Its totient is φ = 616635996.

The previous prime is 616635989. The next prime is 616636061. The reversal of 616635997 is 799536616.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 464014681 + 152621316 = 21541^2 + 12354^2 .

It is a cyclic number.

It is not a de Polignac number, because 616635997 - 2³ = 616635989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (616635197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 308317998 + 308317999.

It is an arithmetic number, because the mean of its divisors is an integer number (308317999).

Almost surely, 2^616635997 is an apocalyptic number.

It is an amenable number.

616635997 is a deficient number, since it is larger than the sum of its proper divisors (1).

616635997 is an equidigital number, since it uses as much as digits as its factorization.

616635997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1837080, while the sum is 52.

The square root of 616635997 is about 24832.1565112658. The cubic root of 616635997 is about 851.1569007991.

The spelling of 616635997 in words is "six hundred sixteen million, six hundred thirty-five thousand, nine hundred ninety-seven".