213122091 has 16 divisors (see below), whose sum is σ = 349739264. Its totient is φ = 112415904.

The previous prime is 213122089. The next prime is 213122093. The reversal of 213122091 is 190221312.

It is an interprime number because it is at equal distance from previous prime (213122089) and next prime (213122093).

It is not a de Polignac number, because 213122091 - 2¹ = 213122089 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (213122093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 390061 + ... + 390606.

It is an arithmetic number, because the mean of its divisors is an integer number (21858704).

Almost surely, 2^213122091 is an apocalyptic number.

213122091 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

213122091 is a deficient number, since it is larger than the sum of its proper divisors (136617173).

213122091 is a wasteful number, since it uses less digits than its factorization.

213122091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780690.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 213122091 is about 14598.7016888489. The cubic root of 213122091 is about 597.3233464100.

The spelling of 213122091 in words is "two hundred thirteen million, one hundred twenty-two thousand, ninety-one".