215131 has 8 divisors (see below), whose sum is σ = 249824. Its totient is φ = 181440.

The previous prime is 215123. The next prime is 215141. The reversal of 215131 is 131512.

215131 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 215131 - 2³ = 215123 is a prime.

It is a super-2 number, since 2×215131² = 92562694322, which contains 22 as substring.

It is a Duffinian number.

215131 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (215141) 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, 301 + ... + 721.

It is an arithmetic number, because the mean of its divisors is an integer number (31228).

2²¹⁵¹³¹ is an apocalyptic number.

215131 is a deficient number, since it is larger than the sum of its proper divisors (34693).

215131 is an equidigital number, since it uses as much as digits as its factorization.

215131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501.

The product of its digits is 30, while the sum is 13.

The square root of 215131 is about 463.8221641966. The cubic root of 215131 is about 59.9194288904.

Adding to 215131 its reverse (131512), we get a palindrome (346643).

The spelling of 215131 in words is "two hundred fifteen thousand, one hundred thirty-one".