400393521024 has 128 divisors (see below), whose sum is σ = 1216145249280. Its totient is φ = 114335569920.

The previous prime is 400393521007. The next prime is 400393521041. The reversal of 400393521024 is 420125393004.

It is an interprime number because it is at equal distance from previous prime (400393521007) and next prime (400393521041).

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4989442 + ... + 5069054.

It is an arithmetic number, because the mean of its divisors is an integer number (9501134760).

Almost surely, 2^400393521024 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400393521024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (608072624640).

400393521024 is an abundant number, since it is smaller than the sum of its proper divisors (815751728256).

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

400393521024 is a wasteful number, since it uses less digits than its factorization.

400393521024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81508 (or 81496 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 33.

The spelling of 400393521024 in words is "four hundred billion, three hundred ninety-three million, five hundred twenty-one thousand, twenty-four".