2157213 has 4 divisors (see below), whose sum is σ = 2876288. Its totient is φ = 1438140.

The previous prime is 2157209. The next prime is 2157229. The reversal of 2157213 is 3127512.

2157213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2157213 - 2² = 2157209 is a prime.

It is a D-number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2157213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157293) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 359533 + ... + 359538.

It is an arithmetic number, because the mean of its divisors is an integer number (719072).

2^2157213 is an apocalyptic number.

It is an amenable number.

2157213 is a deficient number, since it is larger than the sum of its proper divisors (719075).

2157213 is an equidigital number, since it uses as much as digits as its factorization.

2157213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719074.

The product of its digits is 420, while the sum is 21.

The square root of 2157213 is about 1468.7453829715. The cubic root of 2157213 is about 129.2104610891.

Subtracting 2157213 from its reverse (3127512), we obtain a cube (970299 = 99³).

The spelling of 2157213 in words is "two million, one hundred fifty-seven thousand, two hundred thirteen".