381218215 has 32 divisors (see below), whose sum is σ = 560332800. Its totient is φ = 243264384.

The previous prime is 381218197. The next prime is 381218221. The reversal of 381218215 is 512812183.

It is a cyclic number.

It is not a de Polignac number, because 381218215 - 2¹⁵ = 381185447 is a prime.

It is a congruent number.

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, 23386 + ... + 36184.

It is an arithmetic number, because the mean of its divisors is an integer number (17510400).

Almost surely, 2^381218215 is an apocalyptic number.

381218215 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

381218215 is a deficient number, since it is larger than the sum of its proper divisors (179114585).

381218215 is a wasteful number, since it uses less digits than its factorization.

381218215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12871.

The product of its digits is 3840, while the sum is 31.

The square root of 381218215 is about 19524.8102423557. The cubic root of 381218215 is about 725.0888293854.

The spelling of 381218215 in words is "three hundred eighty-one million, two hundred eighteen thousand, two hundred fifteen".