399123901 has 4 divisors (see below), whose sum is σ = 435407904. Its totient is φ = 362839900.

The previous prime is 399123887. The next prime is 399123913. The reversal of 399123901 is 109321993.

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 399123901 - 2⁵ = 399123869 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 (399123931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18141985 + ... + 18142006.

It is an arithmetic number, because the mean of its divisors is an integer number (108851976).

Almost surely, 2^399123901 is an apocalyptic number.

It is an amenable number.

399123901 is a deficient number, since it is larger than the sum of its proper divisors (36284003).

399123901 is a wasteful number, since it uses less digits than its factorization.

399123901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36284002.

The product of its (nonzero) digits is 13122, while the sum is 37.

The square root of 399123901 is about 19978.0855188879. The cubic root of 399123901 is about 736.2679771313.

The spelling of 399123901 in words is "three hundred ninety-nine million, one hundred twenty-three thousand, nine hundred one".