19875217 has 2 divisors, whose sum is σ = 19875218. Its totient is φ = 19875216.

The previous prime is 19875211. The next prime is 19875221. The reversal of 19875217 is 71257891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18584721 + 1290496 = 4311^2 + 1136^2 .

It is an emirp because it is prime and its reverse (71257891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19875217 - 2³ = 19875209 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19875217.

It is not a weakly prime, because it can be changed into another prime (19875211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9937608 + 9937609.

It is an arithmetic number, because the mean of its divisors is an integer number (9937609).

Almost surely, 2^19875217 is an apocalyptic number.

It is an amenable number.

19875217 is a deficient number, since it is larger than the sum of its proper divisors (1).

19875217 is an equidigital number, since it uses as much as digits as its factorization.

19875217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 35280, while the sum is 40.

The square root of 19875217 is about 4458.1629624768. The cubic root of 19875217 is about 270.8760615715.

The spelling of 19875217 in words is "nineteen million, eight hundred seventy-five thousand, two hundred seventeen".