109991015 has 4 divisors (see below), whose sum is σ = 131989224. Its totient is φ = 87992808.

The previous prime is 109990963. The next prime is 109991027. The reversal of 109991015 is 510199901.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 510199901 = 1187 ⋅429823.

It is a cyclic number.

It is not a de Polignac number, because 109991015 - 2¹⁶ = 109925479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10999097 + ... + 10999106.

It is an arithmetic number, because the mean of its divisors is an integer number (32997306).

Almost surely, 2^109991015 is an apocalyptic number.

109991015 is a deficient number, since it is larger than the sum of its proper divisors (21998209).

109991015 is an equidigital number, since it uses as much as digits as its factorization.

109991015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21998208.

The product of its (nonzero) digits is 3645, while the sum is 35.

The square root of 109991015 is about 10487.6601298860. The cubic root of 109991015 is about 479.1289396215.

The spelling of 109991015 in words is "one hundred nine million, nine hundred ninety-one thousand, fifteen".