21352885 has 8 divisors (see below), whose sum is σ = 26316216. Its totient is φ = 16620480.

The previous prime is 21352883. The next prime is 21352907. The reversal of 21352885 is 58825312.

It can be written as a sum of positive squares in 4 ways, for example, as 5280804 + 16072081 = 2298^2 + 4009^2 .

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

It is not a de Polignac number, because 21352885 - 2¹ = 21352883 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21352885.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21352883) 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, 57526 + ... + 57895.

It is an arithmetic number, because the mean of its divisors is an integer number (3289527).

Almost surely, 2^21352885 is an apocalyptic number.

It is an amenable number.

21352885 is a deficient number, since it is larger than the sum of its proper divisors (4963331).

21352885 is a wasteful number, since it uses less digits than its factorization.

21352885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115463.

The product of its digits is 19200, while the sum is 34.

The square root of 21352885 is about 4620.9181987999. The cubic root of 21352885 is about 277.4292111729.

The spelling of 21352885 in words is "twenty-one million, three hundred fifty-two thousand, eight hundred eighty-five".