21266693 has 8 divisors (see below), whose sum is σ = 24336960. Its totient is φ = 18204480.

The previous prime is 21266669. The next prime is 21266731. The reversal of 21266693 is 39666212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21266693 - 2⁶ = 21266629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21266603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5558 + ... + 8568.

It is an arithmetic number, because the mean of its divisors is an integer number (3042120).

Almost surely, 2^21266693 is an apocalyptic number.

It is an amenable number.

21266693 is a deficient number, since it is larger than the sum of its proper divisors (3070267).

21266693 is a wasteful number, since it uses less digits than its factorization.

21266693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4027.

The product of its digits is 23328, while the sum is 35.

The square root of 21266693 is about 4611.5824832697. The cubic root of 21266693 is about 277.0554221017.

The spelling of 21266693 in words is "twenty-one million, two hundred sixty-six thousand, six hundred ninety-three".