21873673 has 2 divisors, whose sum is σ = 21873674. Its totient is φ = 21873672.

The previous prime is 21873641. The next prime is 21873707. The reversal of 21873673 is 37637812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11614464 + 10259209 = 3408^2 + 3203^2 .

It is a cyclic number.

It is not a de Polignac number, because 21873673 - 2⁵ = 21873641 is a prime.

It is not a weakly prime, because it can be changed into another prime (21873613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10936836 + 10936837.

It is an arithmetic number, because the mean of its divisors is an integer number (10936837).

Almost surely, 2^21873673 is an apocalyptic number.

It is an amenable number.

21873673 is a deficient number, since it is larger than the sum of its proper divisors (1).

21873673 is an equidigital number, since it uses as much as digits as its factorization.

21873673 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42336, while the sum is 37.

The square root of 21873673 is about 4676.9298690487. The cubic root of 21873673 is about 279.6665801670. Note that the first 3 decimals are identical.

The spelling of 21873673 in words is "twenty-one million, eight hundred seventy-three thousand, six hundred seventy-three".