400821568 has 168 divisors, whose sum is σ = 1008888000. Its totient is φ = 157489920.

The previous prime is 400821559. The next prime is 400821581. The reversal of 400821568 is 865128004.

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, 12929713 + ... + 12929743.

Almost surely, 2^400821568 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 400821568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (504444000).

400821568 is an abundant number, since it is smaller than the sum of its proper divisors (608066432).

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

400821568 is an equidigital number, since it uses as much as digits as its factorization.

400821568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 34.

The square root of 400821568 is about 20020.5286643485. The cubic root of 400821568 is about 737.3104018220.

The spelling of 400821568 in words is "four hundred million, eight hundred twenty-one thousand, five hundred sixty-eight".