19867973 has 2 divisors, whose sum is σ = 19867974. Its totient is φ = 19867972.

The previous prime is 19867957. The next prime is 19868003. The reversal of 19867973 is 37976891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17656804 + 2211169 = 4202^2 + 1487^2 .

It is a cyclic number.

It is not a de Polignac number, because 19867973 - 2⁴ = 19867957 is a prime.

It is a super-2 number, since 2×19867973² = 789472702257458, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19867933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9933986 + 9933987.

It is an arithmetic number, because the mean of its divisors is an integer number (9933987).

Almost surely, 2^19867973 is an apocalyptic number.

It is an amenable number.

19867973 is a deficient number, since it is larger than the sum of its proper divisors (1).

19867973 is an equidigital number, since it uses as much as digits as its factorization.

19867973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 571536, while the sum is 50.

The square root of 19867973 is about 4457.3504461732. The cubic root of 19867973 is about 270.8431484780.

It can be divided in two parts, 1986 and 7973, that multiplied together give a triangular number (15834378 = T₅₆₂₇).

The spelling of 19867973 in words is "nineteen million, eight hundred sixty-seven thousand, nine hundred seventy-three".