399507323905 has 4 divisors (see below), whose sum is σ = 479408788692. Its totient is φ = 319605859120.

The previous prime is 399507323903. The next prime is 399507323981. The reversal of 399507323905 is 509323705993.

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 97553776896 + 301953547009 = 312336^2 + 549503^2 .

It is not a de Polignac number, because 399507323905 - 2¹ = 399507323903 is a prime.

It is a super-2 number, since 2×399507323905² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399507323903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39950732386 + ... + 39950732395.

It is an arithmetic number, because the mean of its divisors is an integer number (119852197173).

Almost surely, 2^399507323905 is an apocalyptic number.

It is an amenable number.

399507323905 is a deficient number, since it is larger than the sum of its proper divisors (79901464787).

399507323905 is an equidigital number, since it uses as much as digits as its factorization.

399507323905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79901464786.

The product of its (nonzero) digits is 6889050, while the sum is 55.

The spelling of 399507323905 in words is "three hundred ninety-nine billion, five hundred seven million, three hundred twenty-three thousand, nine hundred five".