991742679 has 12 divisors (see below), whose sum is σ = 1433003832. Its totient is φ = 660937200.

The previous prime is 991742671. The next prime is 991742683. The reversal of 991742679 is 976247199.

It is not a de Polignac number, because 991742679 - 2³ = 991742671 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991742671) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11884 + ... + 46094.

It is an arithmetic number, because the mean of its divisors is an integer number (119416986).

Almost surely, 2^991742679 is an apocalyptic number.

991742679 is a deficient number, since it is larger than the sum of its proper divisors (441261153).

991742679 is a wasteful number, since it uses less digits than its factorization.

991742679 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37438 (or 37435 counting only the distinct ones).

The product of its digits is 1714608, while the sum is 54.

The square root of 991742679 is about 31491.9462561462. The cubic root of 991742679 is about 997.2399487926.

The spelling of 991742679 in words is "nine hundred ninety-one million, seven hundred forty-two thousand, six hundred seventy-nine".