399072769 has 4 divisors (see below), whose sum is σ = 399205296. Its totient is φ = 398940244.

The previous prime is 399072763. The next prime is 399072811. The reversal of 399072769 is 967270993.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 399072769 - 2³ = 399072761 is a prime.

It is a super-2 number, since 2×399072769² = 318518149914654722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399072761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61639 + ... + 67804.

It is an arithmetic number, because the mean of its divisors is an integer number (99801324).

Almost surely, 2^399072769 is an apocalyptic number.

It is an amenable number.

399072769 is a deficient number, since it is larger than the sum of its proper divisors (132527).

399072769 is a wasteful number, since it uses less digits than its factorization.

399072769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132526.

The product of its (nonzero) digits is 1285956, while the sum is 52.

The square root of 399072769 is about 19976.8057756990. The cubic root of 399072769 is about 736.2365345460.

The spelling of 399072769 in words is "three hundred ninety-nine million, seventy-two thousand, seven hundred sixty-nine".