19888641 has 6 divisors (see below), whose sum is σ = 28728050. Its totient is φ = 13259088.

The previous prime is 19888601. The next prime is 19888651. The reversal of 19888641 is 14688891.

It can be written as a sum of positive squares in only one way, i.e., 19847025 + 41616 = 4455^2 + 204^2 .

It is not a de Polignac number, because 19888641 - 2¹⁵ = 19855873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19888601) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1104916 + ... + 1104933.

Almost surely, 2^19888641 is an apocalyptic number.

It is an amenable number.

19888641 is a deficient number, since it is larger than the sum of its proper divisors (8839409).

19888641 is a wasteful number, since it uses less digits than its factorization.

19888641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2209855 (or 2209852 counting only the distinct ones).

The product of its digits is 110592, while the sum is 45.

The square root of 19888641 is about 4459.6682612051. The cubic root of 19888641 is about 270.9370323424.

The spelling of 19888641 in words is "nineteen million, eight hundred eighty-eight thousand, six hundred forty-one".