1009191000 has 64 divisors (see below), whose sum is σ = 3148685280. Its totient is φ = 269116800.

The previous prime is 1009190977. The next prime is 1009191011. The reversal of 1009191000 is 1919001.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 165199 + ... + 171198.

Almost surely, 2^1009191000 is an apocalyptic number.

1009191000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1009191000 is an abundant number, since it is smaller than the sum of its proper divisors (2139494280).

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

1009191000 is a wasteful number, since it uses less digits than its factorization.

1009191000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336421 (or 336407 counting only the distinct ones).

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

The square root of 1009191000 is about 31767.7666825983. The cubic root of 1009191000 is about 1003.0543282478.

The spelling of 1009191000 in words is "one billion, nine million, one hundred ninety-one thousand".