390390881 has 2 divisors, whose sum is σ = 390390882. Its totient is φ = 390390880.

The previous prime is 390390827. The next prime is 390390887. The reversal of 390390881 is 188093093.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 385729600 + 4661281 = 19640^2 + 2159^2 .

It is a cyclic number.

It is not a de Polignac number, because 390390881 - 2⁶ = 390390817 is a prime.

It is a super-2 number, since 2×390390881² = 304810079935912322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (390390887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195195440 + 195195441.

It is an arithmetic number, because the mean of its divisors is an integer number (195195441).

Almost surely, 2^390390881 is an apocalyptic number.

It is an amenable number.

390390881 is a deficient number, since it is larger than the sum of its proper divisors (1).

390390881 is an equidigital number, since it uses as much as digits as its factorization.

390390881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 390390881 is about 19758.3116940694. The cubic root of 390390881 is about 730.8583641706.

The spelling of 390390881 in words is "three hundred ninety million, three hundred ninety thousand, eight hundred eighty-one".