213155091 has 16 divisors (see below), whose sum is σ = 332406400. Its totient is φ = 134623944.

The previous prime is 213155083. The next prime is 213155093. The reversal of 213155091 is 190551312.

213155091 is a `hidden beast` number, since 21 + 3 + 1 + 550 + 91 = 666.

It is not a de Polignac number, because 213155091 - 2³ = 213155083 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213155093) 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, 207241 + ... + 208266.

It is an arithmetic number, because the mean of its divisors is an integer number (20775400).

Almost surely, 2^213155091 is an apocalyptic number.

213155091 is a deficient number, since it is larger than the sum of its proper divisors (119251309).

213155091 is a wasteful number, since it uses less digits than its factorization.

213155091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415535 (or 415529 counting only the distinct ones).

The product of its (nonzero) digits is 1350, while the sum is 27.

The square root of 213155091 is about 14599.8318825937. The cubic root of 213155091 is about 597.3541748318.

The spelling of 213155091 in words is "two hundred thirteen million, one hundred fifty-five thousand, ninety-one".