659491997 has 2 divisors, whose sum is σ = 659491998. Its totient is φ = 659491996.

The previous prime is 659491993. The next prime is 659492003. The reversal of 659491997 is 799194956.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 622452601 + 37039396 = 24949^2 + 6086^2 .

It is a cyclic number.

It is not a de Polignac number, because 659491997 - 2² = 659491993 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (659491993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 329745998 + 329745999.

It is an arithmetic number, because the mean of its divisors is an integer number (329745999).

Almost surely, 2^659491997 is an apocalyptic number.

It is an amenable number.

659491997 is a deficient number, since it is larger than the sum of its proper divisors (1).

659491997 is an equidigital number, since it uses as much as digits as its factorization.

659491997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5511240, while the sum is 59.

The square root of 659491997 is about 25680.5762591107. The cubic root of 659491997 is about 870.4353293223.

The spelling of 659491997 in words is "six hundred fifty-nine million, four hundred ninety-one thousand, nine hundred ninety-seven".