109509921 has 8 divisors (see below), whose sum is σ = 162236960. Its totient is φ = 73006596.

The previous prime is 109509919. The next prime is 109509929. The reversal of 109509921 is 129905901.

It is not a de Polignac number, because 109509921 - 2¹ = 109509919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (109509929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2027935 + ... + 2027988.

It is an arithmetic number, because the mean of its divisors is an integer number (20279620).

Almost surely, 2^109509921 is an apocalyptic number.

It is an amenable number.

109509921 is a deficient number, since it is larger than the sum of its proper divisors (52727039).

109509921 is an equidigital number, since it uses as much as digits as its factorization.

109509921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4055932 (or 4055926 counting only the distinct ones).

The product of its (nonzero) digits is 7290, while the sum is 36.

The square root of 109509921 is about 10464.6988012078. The cubic root of 109509921 is about 478.4293583868.

The spelling of 109509921 in words is "one hundred nine million, five hundred nine thousand, nine hundred twenty-one".