19438561 has 4 divisors (see below), whose sum is σ = 19631124. Its totient is φ = 19246000.

The previous prime is 19438547. The next prime is 19438567. The reversal of 19438561 is 16583491.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16483600 + 2954961 = 4060^2 + 1719^2 .

It is a cyclic number.

It is not a de Polignac number, because 19438561 - 2¹¹ = 19436513 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19438561.

It is not an unprimeable number, because it can be changed into a prime (19438567) 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, 96130 + ... + 96331.

It is an arithmetic number, because the mean of its divisors is an integer number (4907781).

Almost surely, 2^19438561 is an apocalyptic number.

It is an amenable number.

19438561 is a deficient number, since it is larger than the sum of its proper divisors (192563).

19438561 is a wasteful number, since it uses less digits than its factorization.

19438561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192562.

The product of its digits is 25920, while the sum is 37.

The square root of 19438561 is about 4408.9183480759. The cubic root of 19438561 is about 268.8776501221.

The spelling of 19438561 in words is "nineteen million, four hundred thirty-eight thousand, five hundred sixty-one".