19893561 has 16 divisors (see below), whose sum is σ = 27371520. Its totient is φ = 12845840.

The previous prime is 19893539. The next prime is 19893571. The reversal of 19893561 is 16539891.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19893561 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (19893521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11776 + ... + 13358.

It is an arithmetic number, because the mean of its divisors is an integer number (1710720).

Almost surely, 2^19893561 is an apocalyptic number.

It is an amenable number.

19893561 is a deficient number, since it is larger than the sum of its proper divisors (7477959).

19893561 is a wasteful number, since it uses less digits than its factorization.

19893561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1716.

The product of its digits is 58320, while the sum is 42.

The square root of 19893561 is about 4460.2198376313. The cubic root of 19893561 is about 270.9593717319.

The spelling of 19893561 in words is "nineteen million, eight hundred ninety-three thousand, five hundred sixty-one".