19428817 has 2 divisors, whose sum is σ = 19428818. Its totient is φ = 19428816.

The previous prime is 19428797. The next prime is 19428833. The reversal of 19428817 is 71882491.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18524416 + 904401 = 4304^2 + 951^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19428817 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19428817.

It is not a weakly prime, because it can be changed into another prime (19428517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9714408 + 9714409.

It is an arithmetic number, because the mean of its divisors is an integer number (9714409).

Almost surely, 2^19428817 is an apocalyptic number.

It is an amenable number.

19428817 is a deficient number, since it is larger than the sum of its proper divisors (1).

19428817 is an equidigital number, since it uses as much as digits as its factorization.

19428817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32256, while the sum is 40.

The square root of 19428817 is about 4407.8131766217. The cubic root of 19428817 is about 268.8327156966.

The spelling of 19428817 in words is "nineteen million, four hundred twenty-eight thousand, eight hundred seventeen".