399709128473 has 4 divisors (see below), whose sum is σ = 399712268340. Its totient is φ = 399705988608.

The previous prime is 399709128439. The next prime is 399709128479. The reversal of 399709128473 is 374821907993.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 312203797504 + 87505330969 = 558752^2 + 295813^2 .

It is a cyclic number.

It is not a de Polignac number, because 399709128473 - 2¹⁸ = 399708866329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399709128479) 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, 1370540 + ... + 1636397.

It is an arithmetic number, because the mean of its divisors is an integer number (99928067085).

Almost surely, 2^399709128473 is an apocalyptic number.

It is an amenable number.

399709128473 is a deficient number, since it is larger than the sum of its proper divisors (3139867).

399709128473 is a wasteful number, since it uses less digits than its factorization.

399709128473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3139866.

The product of its (nonzero) digits is 20575296, while the sum is 62.

The spelling of 399709128473 in words is "three hundred ninety-nine billion, seven hundred nine million, one hundred twenty-eight thousand, four hundred seventy-three".