398921659 has 2 divisors, whose sum is σ = 398921660. Its totient is φ = 398921658.

The previous prime is 398921599. The next prime is 398921681. The reversal of 398921659 is 956129893.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 398921659 - 2²³ = 390533051 is a prime.

It is not a weakly prime, because it can be changed into another prime (399921659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199460829 + 199460830.

It is an arithmetic number, because the mean of its divisors is an integer number (199460830).

Almost surely, 2^398921659 is an apocalyptic number.

398921659 is a deficient number, since it is larger than the sum of its proper divisors (1).

398921659 is an equidigital number, since it uses as much as digits as its factorization.

398921659 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1049760, while the sum is 52.

The square root of 398921659 is about 19973.0232814164. The cubic root of 398921659 is about 736.1435968194.

The spelling of 398921659 in words is "three hundred ninety-eight million, nine hundred twenty-one thousand, six hundred fifty-nine".