2791987731 has 64 divisors (see below), whose sum is σ = 4654540800. Its totient is φ = 1642177152.

The previous prime is 2791987703. The next prime is 2791987747. The reversal of 2791987731 is 1377891972.

It is not a de Polignac number, because 2791987731 - 2⁷ = 2791987603 is a prime.

It is a super-2 number, since 2×2791987731² = 15590390980109056722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2791987771) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1047106 + ... + 1049768.

It is an arithmetic number, because the mean of its divisors is an integer number (72727200).

Almost surely, 2^2791987731 is an apocalyptic number.

2791987731 is a deficient number, since it is larger than the sum of its proper divisors (1862553069).

2791987731 is a wasteful number, since it uses less digits than its factorization.

2791987731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2817 (or 2811 counting only the distinct ones).

The product of its digits is 1333584, while the sum is 54.

The square root of 2791987731 is about 52839.2631572394. The cubic root of 2791987731 is about 1408.1140607589.

The spelling of 2791987731 in words is "two billion, seven hundred ninety-one million, nine hundred eighty-seven thousand, seven hundred thirty-one".