12787191765 has 40 divisors (see below), whose sum is σ = 22938382368. Its totient is φ = 6815028960.

The previous prime is 12787191761. The next prime is 12787191793. The reversal of 12787191765 is 56719178721.

It is not a de Polignac number, because 12787191765 - 2² = 12787191761 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12787191761) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 606450 + ... + 627180.

Almost surely, 2^12787191765 is an apocalyptic number.

12787191765 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12787191765 is a deficient number, since it is larger than the sum of its proper divisors (10151190603).

12787191765 is a wasteful number, since it uses less digits than its factorization.

12787191765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22271 (or 22262 counting only the distinct ones).

The product of its digits is 1481760, while the sum is 54.

The spelling of 12787191765 in words is "twelve billion, seven hundred eighty-seven million, one hundred ninety-one thousand, seven hundred sixty-five".