12127991785 has 48 divisors (see below), whose sum is σ = 18037416960. Its totient is φ = 7665166080.

The previous prime is 12127991767. The next prime is 12127991809. The reversal of 12127991785 is 58719972121.

It is not a de Polignac number, because 12127991785 - 2¹⁵ = 12127959017 is a prime.

It is a hoax number, since the sum of its digits (52) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5860731 + ... + 5862799.

It is an arithmetic number, because the mean of its divisors is an integer number (375779520).

Almost surely, 2^12127991785 is an apocalyptic number.

It is an amenable number.

12127991785 is a deficient number, since it is larger than the sum of its proper divisors (5909425175).

12127991785 is a wasteful number, since it uses less digits than its factorization.

12127991785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3098 (or 3085 counting only the distinct ones).

The product of its digits is 635040, while the sum is 52.

It can be divided in two parts, 1212 and 7991785, that added together give a palindrome (7992997).

The spelling of 12127991785 in words is "twelve billion, one hundred twenty-seven million, nine hundred ninety-one thousand, seven hundred eighty-five".