109785391 has 2 divisors, whose sum is σ = 109785392. Its totient is φ = 109785390.

The previous prime is 109785323. The next prime is 109785409. The reversal of 109785391 is 193587901.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 109785391 - 2²³ = 101396783 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (109785311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54892695 + 54892696.

It is an arithmetic number, because the mean of its divisors is an integer number (54892696).

Almost surely, 2^109785391 is an apocalyptic number.

109785391 is a deficient number, since it is larger than the sum of its proper divisors (1).

109785391 is an equidigital number, since it uses as much as digits as its factorization.

109785391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 68040, while the sum is 43.

The square root of 109785391 is about 10477.8524039996. The cubic root of 109785391 is about 478.8301822903.

The spelling of 109785391 in words is "one hundred nine million, seven hundred eighty-five thousand, three hundred ninety-one".