213121091 has 8 divisors (see below), whose sum is σ = 218474640. Its totient is φ = 207833472.

The previous prime is 213121079. The next prime is 213121093. The reversal of 213121091 is 190121312.

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 213121091 - 2²⁶ = 146012227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213121093) 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, 9905 + ... + 22898.

It is an arithmetic number, because the mean of its divisors is an integer number (27309330).

Almost surely, 2^213121091 is an apocalyptic number.

213121091 is a deficient number, since it is larger than the sum of its proper divisors (5353549).

213121091 is an equidigital number, since it uses as much as digits as its factorization.

213121091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32965.

The product of its (nonzero) digits is 108, while the sum is 20.

The square root of 213121091 is about 14598.6674391877. The cubic root of 213121091 is about 597.3224121657.

The spelling of 213121091 in words is "two hundred thirteen million, one hundred twenty-one thousand, ninety-one".