381890905 has 16 divisors (see below), whose sum is σ = 503875584. Its totient is φ = 275546880.

The previous prime is 381890881. The next prime is 381890909. The reversal of 381890905 is 509098183.

It is not a de Polignac number, because 381890905 - 2⁷ = 381890777 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (381890909) 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, 20352 + ... + 34321.

It is an arithmetic number, because the mean of its divisors is an integer number (31492224).

Almost surely, 2^381890905 is an apocalyptic number.

It is an amenable number.

381890905 is a deficient number, since it is larger than the sum of its proper divisors (121984679).

381890905 is a wasteful number, since it uses less digits than its factorization.

381890905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54816.

The product of its (nonzero) digits is 77760, while the sum is 43.

The square root of 381890905 is about 19542.0291935101. The cubic root of 381890905 is about 725.5150711626.

The spelling of 381890905 in words is "three hundred eighty-one million, eight hundred ninety thousand, nine hundred five".