991484890 has 24 divisors (see below), whose sum is σ = 1961667540. Its totient is φ = 360539520.

The previous prime is 991484869. The next prime is 991484909. The reversal of 991484890 is 98484199.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 946608289 + 44876601 = 30767^2 + 6699^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 408495 + ... + 410914.

Almost surely, 2^991484890 is an apocalyptic number.

991484890 is a deficient number, since it is larger than the sum of its proper divisors (970182650).

991484890 is a wasteful number, since it uses less digits than its factorization.

991484890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 819438 (or 819427 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 52.

The square root of 991484890 is about 31487.8530547892. The cubic root of 991484890 is about 997.1535353266.

The spelling of 991484890 in words is "nine hundred ninety-one million, four hundred eighty-four thousand, eight hundred ninety".