399038641 has 2 divisors, whose sum is σ = 399038642. Its totient is φ = 399038640.

The previous prime is 399038617. The next prime is 399038657. The reversal of 399038641 is 146830993.

399038641 is nontrivially palindromic in base 5.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 305026225 + 94012416 = 17465^2 + 9696^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-399038641 is a prime.

It is a super-2 number, since 2×399038641² = 318463674022253762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (399038681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199519320 + 199519321.

It is an arithmetic number, because the mean of its divisors is an integer number (199519321).

Almost surely, 2^399038641 is an apocalyptic number.

It is an amenable number.

399038641 is a deficient number, since it is larger than the sum of its proper divisors (1).

399038641 is an equidigital number, since it uses as much as digits as its factorization.

399038641 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 139968, while the sum is 43.

The square root of 399038641 is about 19975.9515668215. The cubic root of 399038641 is about 736.2155467307.

The spelling of 399038641 in words is "three hundred ninety-nine million, thirty-eight thousand, six hundred forty-one".