381515820 has 96 divisors (see below), whose sum is σ = 1285132800. Its totient is φ = 82612224.

The previous prime is 381515803. The next prime is 381515821. The reversal of 381515820 is 28515183.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (381515821) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15925 + ... + 31884.

It is an arithmetic number, because the mean of its divisors is an integer number (13386800).

Almost surely, 2^381515820 is an apocalyptic number.

381515820 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

381515820 is an abundant number, since it is smaller than the sum of its proper divisors (903616980).

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

381515820 is a wasteful number, since it uses less digits than its factorization.

381515820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47847 (or 47845 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 33.

The square root of 381515820 is about 19532.4299563572. The cubic root of 381515820 is about 725.2774649432.

The spelling of 381515820 in words is "three hundred eighty-one million, five hundred fifteen thousand, eight hundred twenty".