21252887 has 8 divisors (see below), whose sum is σ = 23093760. Its totient is φ = 19484280.

The previous prime is 21252871. The next prime is 21252893. The reversal of 21252887 is 78825212.

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 21252887 - 2⁴ = 21252871 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21252487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17453 + ... + 18630.

It is an arithmetic number, because the mean of its divisors is an integer number (2886720).

Almost surely, 2^21252887 is an apocalyptic number.

21252887 is a deficient number, since it is larger than the sum of its proper divisors (1840873).

21252887 is a wasteful number, since it uses less digits than its factorization.

21252887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36133.

The product of its digits is 17920, while the sum is 35.

The square root of 21252887 is about 4610.0853571273. The cubic root of 21252887 is about 276.9954557939.

The spelling of 21252887 in words is "twenty-one million, two hundred fifty-two thousand, eight hundred eighty-seven".