215117823 has 16 divisors (see below), whose sum is σ = 290941056. Its totient is φ = 141361440.

The previous prime is 215117809. The next prime is 215117839. The reversal of 215117823 is 328711512.

It is not a de Polignac number, because 215117823 - 2¹⁰ = 215116799 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215117803) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 163936 + ... + 165242.

It is an arithmetic number, because the mean of its divisors is an integer number (18183816).

Almost surely, 2^215117823 is an apocalyptic number.

215117823 is a deficient number, since it is larger than the sum of its proper divisors (75823233).

215117823 is a wasteful number, since it uses less digits than its factorization.

215117823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2054.

The product of its digits is 3360, while the sum is 30.

The square root of 215117823 is about 14666.8954792758. The cubic root of 215117823 is about 599.1820548941.

The spelling of 215117823 in words is "two hundred fifteen million, one hundred seventeen thousand, eight hundred twenty-three".