1091090100 has 72 divisors (see below), whose sum is σ = 3294164160. Its totient is φ = 278305280.

The previous prime is 1091090089. The next prime is 1091090111. The reversal of 1091090100 is 10901901.

It is an interprime number because it is at equal distance from previous prime (1091090089) and next prime (1091090111).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 72165 + ... + 85964.

It is an arithmetic number, because the mean of its divisors is an integer number (45752280).

Almost surely, 2^1091090100 is an apocalyptic number.

1091090100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1091090100 is an abundant number, since it is smaller than the sum of its proper divisors (2203074060).

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

1091090100 is a wasteful number, since it uses less digits than its factorization.

1091090100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158169 (or 158162 counting only the distinct ones).

The product of its (nonzero) digits is 81, while the sum is 21.

The square root of 1091090100 is about 33031.6530013259. The cubic root of 1091090100 is about 1029.4854312260.

The spelling of 1091090100 in words is "one billion, ninety-one million, ninety thousand, one hundred".