1021109091 has 16 divisors (see below), whose sum is σ = 1412135328. Its totient is φ = 655776000.

The previous prime is 1021109071. The next prime is 1021109101. The reversal of 1021109091 is 1909011201.

It is not a de Polignac number, because 1021109091 - 2⁶ = 1021109027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1021109021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34330 + ... + 56751.

It is an arithmetic number, because the mean of its divisors is an integer number (88258458).

Almost surely, 2^1021109091 is an apocalyptic number.

1021109091 is a deficient number, since it is larger than the sum of its proper divisors (391026237).

1021109091 is a wasteful number, since it uses less digits than its factorization.

1021109091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91222.

The product of its (nonzero) digits is 162, while the sum is 24.

The square root of 1021109091 is about 31954.7976210146. The cubic root of 1021109091 is about 1006.9874258287.

The spelling of 1021109091 in words is "one billion, twenty-one million, one hundred nine thousand, ninety-one".