399669769 has 8 divisors (see below), whose sum is σ = 426032000. Its totient is φ = 373840272.

The previous prime is 399669761. The next prime is 399669797. The reversal of 399669769 is 967966993.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 399669769 - 2³ = 399669761 is a prime.

It is a super-2 number, since 2×399669769² = 319471848505026722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 399669769.

It is not an unprimeable number, because it can be changed into a prime (399669761) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 131634 + ... + 134635.

It is an arithmetic number, because the mean of its divisors is an integer number (53254000).

Almost surely, 2^399669769 is an apocalyptic number.

It is an amenable number.

399669769 is a deficient number, since it is larger than the sum of its proper divisors (26362231).

399669769 is a wasteful number, since it uses less digits than its factorization.

399669769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266367.

The product of its digits is 29760696, while the sum is 64.

The square root of 399669769 is about 19991.7425203507. The cubic root of 399669769 is about 736.6034803358.

The spelling of 399669769 in words is "three hundred ninety-nine million, six hundred sixty-nine thousand, seven hundred sixty-nine".