3128797687949 has 4 divisors (see below), whose sum is σ = 3149796330300. Its totient is φ = 3107799045600.

The previous prime is 3128797687943. The next prime is 3128797687969. The reversal of 3128797687949 is 9497867978213.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1997939845225 + 1130857842724 = 1413485^2 + 1063418^2 .

It is a cyclic number.

It is not a de Polignac number, because 3128797687949 - 2¹² = 3128797683853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3128797687943) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10499320952 + ... + 10499321249.

It is an arithmetic number, because the mean of its divisors is an integer number (787449082575).

Almost surely, 2^{3128797687949} is an apocalyptic number.

It is an amenable number.

3128797687949 is a deficient number, since it is larger than the sum of its proper divisors (20998642351).

3128797687949 is a wasteful number, since it uses less digits than its factorization.

3128797687949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20998642350.

The product of its digits is 2304433152, while the sum is 80.

The spelling of 3128797687949 in words is "three trillion, one hundred twenty-eight billion, seven hundred ninety-seven million, six hundred eighty-seven thousand, nine hundred forty-nine".