381661504 has 56 divisors (see below), whose sum is σ = 869045760. Its totient is φ = 162909696.

The previous prime is 381661499. The next prime is 381661513. The reversal of 381661504 is 405166183.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (56).

It is a self number, because there is not a number n which added to its sum of digits gives 381661504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118929 + ... + 122095.

Almost surely, 2^381661504 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 381661504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (434522880).

381661504 is an abundant number, since it is smaller than the sum of its proper divisors (487384256).

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

381661504 is a wasteful number, since it uses less digits than its factorization.

381661504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3455 (or 3445 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 381661504 is about 19536.1588855128. The cubic root of 381661504 is about 725.3697703125.

The spelling of 381661504 in words is "three hundred eighty-one million, six hundred sixty-one thousand, five hundred four".