991488688 has 40 divisors (see below), whose sum is σ = 2077313472. Its totient is φ = 456649728.

The previous prime is 991488679. The next prime is 991488689. The reversal of 991488688 is 886884199.

991488688 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×991488688² = 1966099636863922688, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (991488689) 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, 25995 + ... + 51562.

Almost surely, 2^991488688 is an apocalyptic number.

It is an amenable number.

991488688 is an abundant number, since it is smaller than the sum of its proper divisors (1085824784).

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

991488688 is a wasteful number, since it uses less digits than its factorization.

991488688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77629 (or 77623 counting only the distinct ones).

The product of its digits is 7962624, while the sum is 61.

The square root of 991488688 is about 31487.9133637020. The cubic root of 991488688 is about 997.1548085631.

The spelling of 991488688 in words is "nine hundred ninety-one million, four hundred eighty-eight thousand, six hundred eighty-eight".