381655 has 8 divisors (see below), whose sum is σ = 470592. Its totient is φ = 296928.

The previous prime is 381637. The next prime is 381659. The reversal of 381655 is 556183.

381655 = 83² + 84² + ... + 119².

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 381655 - 2⁷ = 381527 is a prime.

It is an Ulam number.

It is a Duffinian number.

381655 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381659) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 847 + ... + 1216.

It is an arithmetic number, because the mean of its divisors is an integer number (58824).

2³⁸¹⁶⁵⁵ is an apocalyptic number.

381655 is a deficient number, since it is larger than the sum of its proper divisors (88937).

381655 is a wasteful number, since it uses less digits than its factorization.

381655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2105.

The product of its digits is 3600, while the sum is 28.

The square root of 381655 is about 617.7823241240. The cubic root of 381655 is about 72.5365649880.

The spelling of 381655 in words is "three hundred eighty-one thousand, six hundred fifty-five".