19412561 has 4 divisors (see below), whose sum is σ = 22185792. Its totient is φ = 16639332.

The previous prime is 19412539. The next prime is 19412563. The reversal of 19412561 is 16521491.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19412561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19412563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1386605 + ... + 1386618.

It is an arithmetic number, because the mean of its divisors is an integer number (5546448).

Almost surely, 2^19412561 is an apocalyptic number.

It is an amenable number.

19412561 is a deficient number, since it is larger than the sum of its proper divisors (2773231).

19412561 is an equidigital number, since it uses as much as digits as its factorization.

19412561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2773230.

The product of its digits is 2160, while the sum is 29.

The square root of 19412561 is about 4405.9687924451. The cubic root of 19412561 is about 268.7577177520.

The spelling of 19412561 in words is "nineteen million, four hundred twelve thousand, five hundred sixty-one".