398296615921 has 2 divisors, whose sum is σ = 398296615922. Its totient is φ = 398296615920.

The previous prime is 398296615907. The next prime is 398296615931. The reversal of 398296615921 is 129516692893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 325995321600 + 72301294321 = 570960^2 + 268889^2 .

It is a cyclic number.

It is not a de Polignac number, because 398296615921 - 2⁷ = 398296615793 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 398296615921.

It is not a weakly prime, because it can be changed into another prime (398296615931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199148307960 + 199148307961.

It is an arithmetic number, because the mean of its divisors is an integer number (199148307961).

Almost surely, 2^398296615921 is an apocalyptic number.

It is an amenable number.

398296615921 is a deficient number, since it is larger than the sum of its proper divisors (1).

398296615921 is an equidigital number, since it uses as much as digits as its factorization.

398296615921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12597120, while the sum is 61.

The spelling of 398296615921 in words is "three hundred ninety-eight billion, two hundred ninety-six million, six hundred fifteen thousand, nine hundred twenty-one".