215707969 has 9 divisors (see below), whose sum is σ = 227953443. Its totient is φ = 204090552.

The previous prime is 215707963. The next prime is 215708027. The reversal of 215707969 is 969707512.

It is a happy number.

The square root of 215707969 is 14687.

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

215707969 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 13727025 + 201980944 = 3705^2 + 14212^2 .

It is not a de Polignac number, because 215707969 - 2¹¹ = 215705921 is a prime.

It is a super-2 number, since 2×215707969² = 93059855780209922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215707963) 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, 278667 + ... + 279439.

Almost surely, 2^215707969 is an apocalyptic number.

215707969 is the 14687-th square number.

215707969 is the 7344-th centered octagonal number.

It is an amenable number.

215707969 is a deficient number, since it is larger than the sum of its proper divisors (12245474).

215707969 is an frugal number, since it uses more digits than its factorization.

215707969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1584 (or 792 counting only the distinct ones).

The product of its (nonzero) digits is 238140, while the sum is 46.

The cubic root of 215707969 is about 599.7294789749.

The spelling of 215707969 in words is "two hundred fifteen million, seven hundred seven thousand, nine hundred sixty-nine".