399936240 has 120 divisors (see below), whose sum is σ = 1465249968. Its totient is φ = 96952320.

The previous prime is 399936233. The next prime is 399936253. The reversal of 399936240 is 42639993.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17329 + ... + 33168.

Almost surely, 2^399936240 is an apocalyptic number.

399936240 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

399936240 is an abundant number, since it is smaller than the sum of its proper divisors (1065313728).

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

399936240 is a wasteful number, since it uses less digits than its factorization.

399936240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50527 (or 50518 counting only the distinct ones).

The product of its (nonzero) digits is 314928, while the sum is 45.

The square root of 399936240 is about 19998.4059364740. The cubic root of 399936240 is about 736.7671486731.

It can be divided in two parts, 399 and 936240, that added together give a palindrome (936639).

The spelling of 399936240 in words is "three hundred ninety-nine million, nine hundred thirty-six thousand, two hundred forty".