215707161 has 4 divisors (see below), whose sum is σ = 287609552. Its totient is φ = 143804772.

The previous prime is 215707157. The next prime is 215707201. The reversal of 215707161 is 161707512.

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 215707161 - 2² = 215707157 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215707561) 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, 35951191 + ... + 35951196.

It is an arithmetic number, because the mean of its divisors is an integer number (71902388).

Almost surely, 2^215707161 is an apocalyptic number.

It is an amenable number.

215707161 is a deficient number, since it is larger than the sum of its proper divisors (71902391).

215707161 is an equidigital number, since it uses as much as digits as its factorization.

215707161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71902390.

The product of its (nonzero) digits is 2940, while the sum is 30.

The square root of 215707161 is about 14686.9724926548. The cubic root of 215707161 is about 599.7287301507.

The spelling of 215707161 in words is "two hundred fifteen million, seven hundred seven thousand, one hundred sixty-one".