399608540 has 12 divisors (see below), whose sum is σ = 839177976. Its totient is φ = 159843408.

The previous prime is 399608537. The next prime is 399608597. The reversal of 399608540 is 45806993.

It is a junction number, because it is equal to n+sod(n) for n = 399608491 and 399608500.

It is a congruent number.

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, 9990194 + ... + 9990233.

It is an arithmetic number, because the mean of its divisors is an integer number (69931498).

Almost surely, 2^399608540 is an apocalyptic number.

It is an amenable number.

399608540 is an abundant number, since it is smaller than the sum of its proper divisors (439569436).

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

399608540 is a wasteful number, since it uses less digits than its factorization.

399608540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19980436 (or 19980434 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 44.

The square root of 399608540 is about 19990.2111044381. The cubic root of 399608540 is about 736.5658627814.

The spelling of 399608540 in words is "three hundred ninety-nine million, six hundred eight thousand, five hundred forty".