399260960641 has 9 divisors (see below), whose sum is σ = 401594046339. Its totient is φ = 396941362200.

The previous prime is 399260960639. The next prime is 399260960663. The reversal of 399260960641 is 146069062993.

The square root of 399260960641 is 631871.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 4399536241 + 394861424400 = 66329^2 + 628380^2 .

It is not a de Polignac number, because 399260960641 - 2¹ = 399260960639 is a prime.

It is a super-2 number, since 2×399260960641² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399260960941) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 114366906 + ... + 114370396.

Almost surely, 2^399260960641 is an apocalyptic number.

399260960641 is the 631871-st square number.

399260960641 is the 315936-th centered octagonal number.

It is an amenable number.

399260960641 is a deficient number, since it is larger than the sum of its proper divisors (2333085698).

399260960641 is an frugal number, since it uses more digits than its factorization.

399260960641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7344 (or 3672 counting only the distinct ones).

The product of its (nonzero) digits is 3779136, while the sum is 55.

The spelling of 399260960641 in words is "three hundred ninety-nine billion, two hundred sixty million, nine hundred sixty thousand, six hundred forty-one".