213551131 has 4 divisors (see below), whose sum is σ = 213812064. Its totient is φ = 213290200.

The previous prime is 213551123. The next prime is 213551137. The reversal of 213551131 is 131155312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 213551131 - 2³ = 213551123 is a prime.

It is a super-3 number, since 3×213551131³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213551137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 129235 + ... + 130876.

It is an arithmetic number, because the mean of its divisors is an integer number (53453016).

Almost surely, 2^213551131 is an apocalyptic number.

213551131 is a deficient number, since it is larger than the sum of its proper divisors (260933).

213551131 is an equidigital number, since it uses as much as digits as its factorization.

213551131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260932.

The product of its digits is 450, while the sum is 22.

The square root of 213551131 is about 14613.3887582586. The cubic root of 213551131 is about 597.7239052765.

The spelling of 213551131 in words is "two hundred thirteen million, five hundred fifty-one thousand, one hundred thirty-one".