21746693 has 2 divisors, whose sum is σ = 21746694. Its totient is φ = 21746692.

The previous prime is 21746677. The next prime is 21746701. The reversal of 21746693 is 39664712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21696964 + 49729 = 4658^2 + 223^2 .

It is a cyclic number.

It is not a de Polignac number, because 21746693 - 2⁴ = 21746677 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21746623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10873346 + 10873347.

It is an arithmetic number, because the mean of its divisors is an integer number (10873347).

Almost surely, 2^21746693 is an apocalyptic number.

It is an amenable number.

21746693 is a deficient number, since it is larger than the sum of its proper divisors (1).

21746693 is an equidigital number, since it uses as much as digits as its factorization.

21746693 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 21746693 is about 4663.3349654512. The cubic root of 21746693 is about 279.1243605701.

The spelling of 21746693 in words is "twenty-one million, seven hundred forty-six thousand, six hundred ninety-three".