215231361 has 4 divisors (see below), whose sum is σ = 286975152. Its totient is φ = 143487572.

The previous prime is 215231333. The next prime is 215231369. The reversal of 215231361 is 163132512.

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 a cyclic number.

It is not a de Polignac number, because 215231361 - 2⁵ = 215231329 is a prime.

It is not an unprimeable number, because it can be changed into a prime (215231369) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35871891 + ... + 35871896.

It is an arithmetic number, because the mean of its divisors is an integer number (71743788).

Almost surely, 2^215231361 is an apocalyptic number.

It is an amenable number.

215231361 is a deficient number, since it is larger than the sum of its proper divisors (71743791).

215231361 is an equidigital number, since it uses as much as digits as its factorization.

215231361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71743790.

The product of its digits is 1080, while the sum is 24.

The square root of 215231361 is about 14670.7655219487. The cubic root of 215231361 is about 599.2874513479.

Adding to 215231361 its reverse (163132512), we get a palindrome (378363873).

The spelling of 215231361 in words is "two hundred fifteen million, two hundred thirty-one thousand, three hundred sixty-one".