109781939 has 2 divisors, whose sum is σ = 109781940. Its totient is φ = 109781938.

The previous prime is 109781929. The next prime is 109781957. The reversal of 109781939 is 939187901.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 109781939 - 2²⁰ = 108733363 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 109781893 and 109781902.

It is not a weakly prime, because it can be changed into another prime (109781909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54890969 + 54890970.

It is an arithmetic number, because the mean of its divisors is an integer number (54890970).

Almost surely, 2^109781939 is an apocalyptic number.

109781939 is a deficient number, since it is larger than the sum of its proper divisors (1).

109781939 is an equidigital number, since it uses as much as digits as its factorization.

109781939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 122472, while the sum is 47.

The square root of 109781939 is about 10477.6876742915. The cubic root of 109781939 is about 478.8251635925.

The spelling of 109781939 in words is "one hundred nine million, seven hundred eighty-one thousand, nine hundred thirty-nine".