21669263 has 8 divisors (see below), whose sum is σ = 27016320. Its totient is φ = 16885080.

The previous prime is 21669259. The next prime is 21669269. The reversal of 21669263 is 36296612.

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

It is a cyclic number.

It is not a de Polignac number, because 21669263 - 2² = 21669259 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 (21669269) 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 in 7 ways as a sum of consecutive naturals, for example, 140633 + ... + 140786.

It is an arithmetic number, because the mean of its divisors is an integer number (3377040).

Almost surely, 2^21669263 is an apocalyptic number.

21669263 is a deficient number, since it is larger than the sum of its proper divisors (5347057).

21669263 is a wasteful number, since it uses less digits than its factorization.

21669263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281437.

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

The square root of 21669263 is about 4655.0255638396. The cubic root of 21669263 is about 278.7926886702.

The spelling of 21669263 in words is "twenty-one million, six hundred sixty-nine thousand, two hundred sixty-three".