215605134889 has 9 divisors (see below), whose sum is σ = 219774997029. Its totient is φ = 211512968160.

The previous prime is 215605134883. The next prime is 215605134967. The reversal of 215605134889 is 988431506512.

It is a happy number.

The square root of 215605134889 is 464333.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 15177008025 + 200428126864 = 123195^2 + 447692^2 .

It is not a de Polignac number, because 215605134889 - 2⁹ = 215605134377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215605134883) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 24605269 + ... + 24614029.

Almost surely, 2^215605134889 is an apocalyptic number.

215605134889 is the 464333-rd square number.

215605134889 is the 232167-th centered octagonal number.

It is an amenable number.

215605134889 is a deficient number, since it is larger than the sum of its proper divisors (4169862140).

215605134889 is an frugal number, since it uses more digits than its factorization.

215605134889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17628 (or 8814 counting only the distinct ones).

The product of its (nonzero) digits is 2073600, while the sum is 52.

The spelling of 215605134889 in words is "two hundred fifteen billion, six hundred five million, one hundred thirty-four thousand, eight hundred eighty-nine".