291117988 has 24 divisors (see below), whose sum is σ = 586152000. Its totient is φ = 123925728.

The previous prime is 291117949. The next prime is 291118027. The reversal of 291117988 is 889711192.

It is an interprime number because it is at equal distance from previous prime (291117949) and next prime (291118027).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30718 + ... + 39061.

It is an arithmetic number, because the mean of its divisors is an integer number (24423000).

Almost surely, 2^291117988 is an apocalyptic number.

291117988 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

291117988 is an abundant number, since it is smaller than the sum of its proper divisors (295034012).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

291117988 is a wasteful number, since it uses less digits than its factorization.

291117988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69939 (or 69937 counting only the distinct ones).

The product of its digits is 72576, while the sum is 46.

The square root of 291117988 is about 17062.1800482822. The cubic root of 291117988 is about 662.7600881254.

The spelling of 291117988 in words is "two hundred ninety-one million, one hundred seventeen thousand, nine hundred eighty-eight".