19101985 has 16 divisors (see below), whose sum is σ = 26352000. Its totient is φ = 13021056.

The previous prime is 19101917. The next prime is 19101989. The reversal of 19101985 is 58910191.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19101985 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19101985.

It is not an unprimeable number, because it can be changed into a prime (19101989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4741 + ... + 7789.

It is an arithmetic number, because the mean of its divisors is an integer number (1647000).

Almost surely, 2^19101985 is an apocalyptic number.

It is an amenable number.

19101985 is a deficient number, since it is larger than the sum of its proper divisors (7250015).

19101985 is a wasteful number, since it uses less digits than its factorization.

19101985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3240.

The product of its (nonzero) digits is 3240, while the sum is 34.

The square root of 19101985 is about 4370.5817690555. The cubic root of 19101985 is about 267.3167464137.

The spelling of 19101985 in words is "nineteen million, one hundred one thousand, nine hundred eighty-five".