381557520 has 160 divisors (see below), whose sum is σ = 1391696640. Its totient is φ = 95754240.

The previous prime is 381557489. The next prime is 381557581. The reversal of 381557520 is 25755183.

381557520 is a `hidden beast` number, since 3 + 81 + 5 + 57 + 520 = 666.

It is a super-2 number, since 2×381557520² = 291172282137100800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31525 + ... + 41915.

It is an arithmetic number, because the mean of its divisors is an integer number (8698104).

Almost surely, 2^381557520 is an apocalyptic number.

381557520 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 381557520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (695848320).

381557520 is an abundant number, since it is smaller than the sum of its proper divisors (1010139120).

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

381557520 is a wasteful number, since it uses less digits than its factorization.

381557520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10430 (or 10418 counting only the distinct ones).

The product of its (nonzero) digits is 42000, while the sum is 36.

The square root of 381557520 is about 19533.4973827013. The cubic root of 381557520 is about 725.3038884595.

The spelling of 381557520 in words is "three hundred eighty-one million, five hundred fifty-seven thousand, five hundred twenty".