398077681 has 2 divisors, whose sum is σ = 398077682. Its totient is φ = 398077680.

The previous prime is 398077679. The next prime is 398077697. The reversal of 398077681 is 186770893.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 228010000 + 170067681 = 15100^2 + 13041^2 .

It is a cyclic number.

It is not a de Polignac number, because 398077681 - 2¹ = 398077679 is a prime.

It is a super-2 number, since 2×398077681² = 316931680220675522, which contains 22 as substring.

Together with 398077679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (398077601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199038840 + 199038841.

It is an arithmetic number, because the mean of its divisors is an integer number (199038841).

Almost surely, 2^398077681 is an apocalyptic number.

It is an amenable number.

398077681 is a deficient number, since it is larger than the sum of its proper divisors (1).

398077681 is an equidigital number, since it uses as much as digits as its factorization.

398077681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 508032, while the sum is 49.

The square root of 398077681 is about 19951.8841466163. The cubic root of 398077681 is about 735.6240899226.

The spelling of 398077681 in words is "three hundred ninety-eight million, seventy-seven thousand, six hundred eighty-one".