109691581 has 4 divisors (see below), whose sum is σ = 112242592. Its totient is φ = 107140572.

The previous prime is 109691563. The next prime is 109691587. The reversal of 109691581 is 185196901.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 109691581 - 2⁹ = 109691069 is a prime.

It is a super-2 number, since 2×109691581² = 24064485884559122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (109691587) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1275441 + ... + 1275526.

It is an arithmetic number, because the mean of its divisors is an integer number (28060648).

Almost surely, 2^109691581 is an apocalyptic number.

It is an amenable number.

109691581 is a deficient number, since it is larger than the sum of its proper divisors (2551011).

109691581 is an equidigital number, since it uses as much as digits as its factorization.

109691581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2551010.

The product of its (nonzero) digits is 19440, while the sum is 40.

The square root of 109691581 is about 10473.3748620013. The cubic root of 109691581 is about 478.6937589791.

The spelling of 109691581 in words is "one hundred nine million, six hundred ninety-one thousand, five hundred eighty-one".