399491938560 has 1152 divisors, whose sum is σ = 1599756189696. Its totient is φ = 83566264320.

The previous prime is 399491938543. The next prime is 399491938589. The reversal of 399491938560 is 65839194993.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a junction number, because it is equal to n+sod(n) for n = 399491938491 and 399491938500.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 593598384 + ... + 593599056.

It is an arithmetic number, because the mean of its divisors is an integer number (1388677248).

Almost surely, 2^399491938560 is an apocalyptic number.

399491938560 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 399491938560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (799878094848).

399491938560 is an abundant number, since it is smaller than the sum of its proper divisors (1200264251136).

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

399491938560 is a wasteful number, since it uses less digits than its factorization.

399491938560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 791 (or 777 counting only the distinct ones).

The product of its (nonzero) digits is 56687040, while the sum is 66.

The spelling of 399491938560 in words is "three hundred ninety-nine billion, four hundred ninety-one million, nine hundred thirty-eight thousand, five hundred sixty".