399143279 has 8 divisors (see below), whose sum is σ = 420576000. Its totient is φ = 377753112.

The previous prime is 399143257. The next prime is 399143281. The reversal of 399143279 is 972341993.

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 399143279 - 2²⁴ = 382366063 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399143209) 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, 9632 + ... + 29850.

It is an arithmetic number, because the mean of its divisors is an integer number (52572000).

Almost surely, 2^399143279 is an apocalyptic number.

399143279 is a deficient number, since it is larger than the sum of its proper divisors (21432721).

399143279 is a wasteful number, since it uses less digits than its factorization.

399143279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21277.

The product of its digits is 367416, while the sum is 47.

The square root of 399143279 is about 19978.5704944073. The cubic root of 399143279 is about 736.2798925373.

The spelling of 399143279 in words is "three hundred ninety-nine million, one hundred forty-three thousand, two hundred seventy-nine".