394657310381 has 2 divisors, whose sum is σ = 394657310382. Its totient is φ = 394657310380.

The previous prime is 394657310273. The next prime is 394657310413. The reversal of 394657310381 is 183013756493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 388733545225 + 5923765156 = 623485^2 + 76966^2 .

It is a cyclic number.

It is not a de Polignac number, because 394657310381 - 2¹⁸ = 394657048237 is a prime.

It is a super-2 number, since 2×394657310381² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (394657310981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 197328655190 + 197328655191.

It is an arithmetic number, because the mean of its divisors is an integer number (197328655191).

Almost surely, 2^394657310381 is an apocalyptic number.

It is an amenable number.

394657310381 is a deficient number, since it is larger than the sum of its proper divisors (1).

394657310381 is an equidigital number, since it uses as much as digits as its factorization.

394657310381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1632960, while the sum is 50.

The spelling of 394657310381 in words is "three hundred ninety-four billion, six hundred fifty-seven million, three hundred ten thousand, three hundred eighty-one".