400091520 has 128 divisors (see below), whose sum is σ = 1283143680. Its totient is φ = 106035200.

The previous prime is 400091507. The next prime is 400091521. The reversal of 400091520 is 25190004.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400091521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 366175 + ... + 367265.

It is an arithmetic number, because the mean of its divisors is an integer number (10024560).

Almost surely, 2^400091520 is an apocalyptic number.

400091520 is a gapful number since it is divisible by the number (40) 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 400091520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (641571840).

400091520 is an abundant number, since it is smaller than the sum of its proper divisors (883052160).

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

400091520 is a wasteful number, since it uses less digits than its factorization.

400091520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1304 (or 1292 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 400091520 is about 20002.2878691414. The cubic root of 400091520 is about 736.8624892034.

The spelling of 400091520 in words is "four hundred million, ninety-one thousand, five hundred twenty".