216100381 has 16 divisors (see below), whose sum is σ = 254862720. Its totient is φ = 179377920.

The previous prime is 216100333. The next prime is 216100397. The reversal of 216100381 is 183001612.

It is a cyclic number.

It is not a de Polignac number, because 216100381 - 2⁷ = 216100253 is a prime.

It is a super-2 number, since 2×216100381² = 93398749336690322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216100321) 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, 37185 + ... + 42601.

It is an arithmetic number, because the mean of its divisors is an integer number (15928920).

Almost surely, 2^216100381 is an apocalyptic number.

It is an amenable number.

216100381 is a deficient number, since it is larger than the sum of its proper divisors (38762339).

216100381 is a wasteful number, since it uses less digits than its factorization.

216100381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5604.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 216100381 is about 14700.3530909975. The cubic root of 216100381 is about 600.0929309760.

Adding to 216100381 its reverse (183001612), we get a palindrome (399101993).

The spelling of 216100381 in words is "two hundred sixteen million, one hundred thousand, three hundred eighty-one".