21366699 has 8 divisors (see below), whose sum is σ = 29183952. Its totient is φ = 13896960.

The previous prime is 21366689. The next prime is 21366713. The reversal of 21366699 is 99666312.

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

It is not a de Polignac number, because 21366699 - 2⁹ = 21366187 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21366699.

It is not an unprimeable number, because it can be changed into a prime (21366619) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86734 + ... + 86979.

It is an arithmetic number, because the mean of its divisors is an integer number (3647994).

Almost surely, 2^21366699 is an apocalyptic number.

21366699 is a deficient number, since it is larger than the sum of its proper divisors (7817253).

21366699 is a wasteful number, since it uses less digits than its factorization.

21366699 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173757.

The product of its digits is 104976, while the sum is 42.

The square root of 21366699 is about 4622.4126817064. The cubic root of 21366699 is about 277.4890248074.

The spelling of 21366699 in words is "twenty-one million, three hundred sixty-six thousand, six hundred ninety-nine".