399526427520 has 768 divisors, whose sum is σ = 1662954209280. Its totient is φ = 87188766720.

The previous prime is 399526427519. The next prime is 399526427551. The reversal of 399526427520 is 25724625993.

399526427520 is a `hidden beast` number, since 3 + 9 + 9 + 52 + 64 + 2 + 7 + 520 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 24765697 + ... + 24781823.

It is an arithmetic number, because the mean of its divisors is an integer number (2165304960).

Almost surely, 2^399526427520 is an apocalyptic number.

399526427520 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 399526427520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (831477104640).

399526427520 is an abundant number, since it is smaller than the sum of its proper divisors (1263427781760).

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

399526427520 is a wasteful number, since it uses less digits than its factorization.

399526427520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16203 (or 16188 counting only the distinct ones).

The product of its (nonzero) digits is 8164800, while the sum is 54.

The spelling of 399526427520 in words is "three hundred ninety-nine billion, five hundred twenty-six million, four hundred twenty-seven thousand, five hundred twenty".