21069885 has 32 divisors (see below), whose sum is σ = 36391680. Its totient is φ = 10370048.

The previous prime is 21069857. The next prime is 21069901. The reversal of 21069885 is 58896012.

It is a cyclic number.

It is not a de Polignac number, because 21069885 - 2⁷ = 21069757 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12736 + ... + 14294.

It is an arithmetic number, because the mean of its divisors is an integer number (1137240).

Almost surely, 2^21069885 is an apocalyptic number.

It is an amenable number.

21069885 is a deficient number, since it is larger than the sum of its proper divisors (15321795).

21069885 is a wasteful number, since it uses less digits than its factorization.

21069885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1637.

The product of its (nonzero) digits is 34560, while the sum is 39.

The square root of 21069885 is about 4590.1944403260. The cubic root of 21069885 is about 276.1981222922.

The spelling of 21069885 in words is "twenty-one million, sixty-nine thousand, eight hundred eighty-five".