991318427 has 8 divisors (see below), whose sum is σ = 1083941040. Its totient is φ = 899112960.

The previous prime is 991318411. The next prime is 991318429. The reversal of 991318427 is 724813199.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 991318427 - 2⁴ = 991318411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (991318429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 99302 + ... + 108827.

It is an arithmetic number, because the mean of its divisors is an integer number (135492630).

Almost surely, 2^991318427 is an apocalyptic number.

991318427 is a deficient number, since it is larger than the sum of its proper divisors (92622613).

991318427 is a wasteful number, since it uses less digits than its factorization.

991318427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208573.

The product of its digits is 108864, while the sum is 44.

The square root of 991318427 is about 31485.2096546934. The cubic root of 991318427 is about 997.0977272953.

The spelling of 991318427 in words is "nine hundred ninety-one million, three hundred eighteen thousand, four hundred twenty-seven".