1272913785 has 160 divisors (see below), whose sum is σ = 2771112960. Its totient is φ = 550540800.

The previous prime is 1272913783. The next prime is 1272913801. The reversal of 1272913785 is 5873192721.

1272913785 is a `hidden beast` number, since 1 + 272 + 9 + 1 + 378 + 5 = 666.

It is not a de Polignac number, because 1272913785 - 2¹ = 1272913783 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 1272913785.

It is not an unprimeable number, because it can be changed into a prime (1272913783) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 1795011 + ... + 1795719.

It is an arithmetic number, because the mean of its divisors is an integer number (17319456).

Almost surely, 2^1272913785 is an apocalyptic number.

1272913785 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1272913785 is an abundant number, since it is smaller than the sum of its proper divisors (1498199175).

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

1272913785 is a wasteful number, since it uses less digits than its factorization.

1272913785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 781 (or 772 counting only the distinct ones).

The product of its digits is 211680, while the sum is 45.

The square root of 1272913785 is about 35677.9173299115. The cubic root of 1272913785 is about 1083.7596974743.

The spelling of 1272913785 in words is "one billion, two hundred seventy-two million, nine hundred thirteen thousand, seven hundred eighty-five".