991346979 has 24 divisors (see below), whose sum is σ = 1541265408. Its totient is φ = 565133520.

The previous prime is 991346977. The next prime is 991346981. The reversal of 991346979 is 979643199.

It is an interprime number because it is at equal distance from previous prime (991346977) and next prime (991346981).

It is not a de Polignac number, because 991346979 - 2¹ = 991346977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (991346971) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55534 + ... + 71180.

It is an arithmetic number, because the mean of its divisors is an integer number (64219392).

Almost surely, 2^991346979 is an apocalyptic number.

991346979 is a deficient number, since it is larger than the sum of its proper divisors (549918429).

991346979 is a wasteful number, since it uses less digits than its factorization.

991346979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16095 (or 16088 counting only the distinct ones).

The product of its digits is 3306744, while the sum is 57.

The square root of 991346979 is about 31485.6630706739. The cubic root of 991346979 is about 997.1073000219.

The spelling of 991346979 in words is "nine hundred ninety-one million, three hundred forty-six thousand, nine hundred seventy-nine".