991671008 has 24 divisors (see below), whose sum is σ = 2019676680. Its totient is φ = 478737280.

The previous prime is 991671007. The next prime is 991671017. The reversal of 991671008 is 800176199.

It is a happy number.

It is a super-2 number, since 2×991671008² = 1966822776215472128, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991671007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 533378 + ... + 535233.

It is an arithmetic number, because the mean of its divisors is an integer number (84153195).

Almost surely, 2^991671008 is an apocalyptic number.

It is an amenable number.

991671008 is an abundant number, since it is smaller than the sum of its proper divisors (1028005672).

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

991671008 is a wasteful number, since it uses less digits than its factorization.

991671008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1068650 (or 1068642 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 41.

The square root of 991671008 is about 31490.8083097275. The cubic root of 991671008 is about 997.2159254555.

The spelling of 991671008 in words is "nine hundred ninety-one million, six hundred seventy-one thousand, eight".