12387022209 has 27 divisors (see below), whose sum is σ = 18715720387. Its totient is φ = 7894073616.

The previous prime is 12387022201. The next prime is 12387022237. The reversal of 12387022209 is 90222078321.

The square root of 12387022209 is 111297.

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

It can be written as a sum of positive squares in only one way, i.e., 7739600625 + 4647421584 = 87975^2 + 68172^2 .

It is not a de Polignac number, because 12387022209 - 2³ = 12387022201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12387022201) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 7678687 + ... + 7680299.

Almost surely, 2^12387022209 is an apocalyptic number.

12387022209 is the 111297-th square number.

12387022209 is the 55649-th centered octagonal number.

It is an amenable number.

12387022209 is a deficient number, since it is larger than the sum of its proper divisors (6328698178).

12387022209 is an frugal number, since it uses more digits than its factorization.

12387022209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3278 (or 1639 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

Multiplying 12387022209 by its sum of digits (36), we get a square (445932799524 = 667782²).

The spelling of 12387022209 in words is "twelve billion, three hundred eighty-seven million, twenty-two thousand, two hundred nine".