399287697220 has 12 divisors (see below), whose sum is σ = 838504164204. Its totient is φ = 159715078880.

The previous prime is 399287697209. The next prime is 399287697233. The reversal of 399287697220 is 22796782993.

It can be written as a sum of positive squares in 2 ways, for example, as 225858760516 + 173428936704 = 475246^2 + 416448^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9982192411 + ... + 9982192450.

It is an arithmetic number, because the mean of its divisors is an integer number (69875347017).

Almost surely, 2^399287697220 is an apocalyptic number.

It is an amenable number.

399287697220 is an abundant number, since it is smaller than the sum of its proper divisors (439216466984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

399287697220 is a wasteful number, since it uses less digits than its factorization.

399287697220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19964384870 (or 19964384868 counting only the distinct ones).

The product of its (nonzero) digits is 41150592, while the sum is 64.

The spelling of 399287697220 in words is "three hundred ninety-nine billion, two hundred eighty-seven million, six hundred ninety-seven thousand, two hundred twenty".