331609997 has 2 divisors, whose sum is σ = 331609998. Its totient is φ = 331609996.

The previous prime is 331609991. The next prime is 331610017. The reversal of 331609997 is 799906133.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 326199721 + 5410276 = 18061^2 + 2326^2 .

It is a cyclic number.

It is not a de Polignac number, because 331609997 - 2⁴ = 331609981 is a prime.

It is a super-2 number, since 2×331609997² = 219930380220680018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (331609991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165804998 + 165804999.

It is an arithmetic number, because the mean of its divisors is an integer number (165804999).

Almost surely, 2^331609997 is an apocalyptic number.

It is an amenable number.

331609997 is a deficient number, since it is larger than the sum of its proper divisors (1).

331609997 is an equidigital number, since it uses as much as digits as its factorization.

331609997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 275562, while the sum is 47.

The square root of 331609997 is about 18210.1619158095. The cubic root of 331609997 is about 692.1643145340.

The spelling of 331609997 in words is "three hundred thirty-one million, six hundred nine thousand, nine hundred ninety-seven".