19665473 has 2 divisors, whose sum is σ = 19665474. Its totient is φ = 19665472.

The previous prime is 19665449. The next prime is 19665493. The reversal of 19665473 is 37456691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17783089 + 1882384 = 4217^2 + 1372^2 .

It is a cyclic number.

It is not a de Polignac number, because 19665473 - 2⁶ = 19665409 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19665473.

It is not a weakly prime, because it can be changed into another prime (19665493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9832736 + 9832737.

It is an arithmetic number, because the mean of its divisors is an integer number (9832737).

Almost surely, 2^19665473 is an apocalyptic number.

It is an amenable number.

19665473 is a deficient number, since it is larger than the sum of its proper divisors (1).

19665473 is an equidigital number, since it uses as much as digits as its factorization.

19665473 is an evil number, because the sum of its binary digits is even.

The product of its digits is 136080, while the sum is 41.

The square root of 19665473 is about 4434.5769809532. The cubic root of 19665473 is about 269.9198344538.

The spelling of 19665473 in words is "nineteen million, six hundred sixty-five thousand, four hundred seventy-three".