109639781 has 16 divisors (see below), whose sum is σ = 117936000. Its totient is φ = 101671680.

The previous prime is 109639757. The next prime is 109639787. The reversal of 109639781 is 187936901.

It is a cyclic number.

It is not a de Polignac number, because 109639781 - 2¹⁰ = 109638757 is a prime.

It is a super-2 number, since 2×109639781² = 24041763155455922, 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 (109639787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 219470 + ... + 219968.

It is an arithmetic number, because the mean of its divisors is an integer number (7371000).

Almost surely, 2^109639781 is an apocalyptic number.

It is an amenable number.

109639781 is a deficient number, since it is larger than the sum of its proper divisors (8296219).

109639781 is a wasteful number, since it uses less digits than its factorization.

109639781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 796.

The product of its (nonzero) digits is 81648, while the sum is 44.

The square root of 109639781 is about 10470.9016326198. The cubic root of 109639781 is about 478.6183954287.

The spelling of 109639781 in words is "one hundred nine million, six hundred thirty-nine thousand, seven hundred eighty-one".