991827000090 has 48 divisors (see below), whose sum is σ = 2578937711688. Its totient is φ = 264467968128.

The previous prime is 991827000089. The next prime is 991827000097. The reversal of 991827000090 is 90000728199.

It can be written as a sum of positive squares in 4 ways, for example, as 957499433361 + 34327566729 = 978519^2 + 185277^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (991827000097) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 866064 + ... + 1653396.

Almost surely, 2^991827000090 is an apocalyptic number.

991827000090 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

991827000090 is an abundant number, since it is smaller than the sum of its proper divisors (1587110711598).

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

991827000090 is a wasteful number, since it uses less digits than its factorization.

991827000090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801343 (or 801340 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 45.

The spelling of 991827000090 in words is "nine hundred ninety-one billion, eight hundred twenty-seven million, ninety", and thus it is an aban number.