12165121072 has 40 divisors (see below), whose sum is σ = 26069036336. Its totient is φ = 5462919936.

The previous prime is 12165121039. The next prime is 12165121079. The reversal of 12165121072 is 27012156121.

It is a self number, because there is not a number n which added to its sum of digits gives 12165121072.

It is not an unprimeable number, because it can be changed into a prime (12165121079) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 782658 + ... + 798049.

Almost surely, 2^12165121072 is an apocalyptic number.

It is an amenable number.

12165121072 is an abundant number, since it is smaller than the sum of its proper divisors (13903915264).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12165121072 is a wasteful number, since it uses less digits than its factorization.

12165121072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1580765 (or 1580759 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 28.

Adding to 12165121072 its reverse (27012156121), we get a palindrome (39177277193).

The spelling of 12165121072 in words is "twelve billion, one hundred sixty-five million, one hundred twenty-one thousand, seventy-two".