21674693 has 2 divisors, whose sum is σ = 21674694. Its totient is φ = 21674692.

The previous prime is 21674683. The next prime is 21674699. The reversal of 21674693 is 39647612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19775809 + 1898884 = 4447^2 + 1378^2 .

It is a cyclic number.

It is not a de Polignac number, because 21674693 - 2¹⁸ = 21412549 is a prime.

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 (21674699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10837346 + 10837347.

It is an arithmetic number, because the mean of its divisors is an integer number (10837347).

Almost surely, 2^21674693 is an apocalyptic number.

It is an amenable number.

21674693 is a deficient number, since it is larger than the sum of its proper divisors (1).

21674693 is an equidigital number, since it uses as much as digits as its factorization.

21674693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54432, while the sum is 38.

The square root of 21674693 is about 4655.6087679271. The cubic root of 21674693 is about 278.8159738471.

The spelling of 21674693 in words is "twenty-one million, six hundred seventy-four thousand, six hundred ninety-three".