21652087 has 8 divisors (see below), whose sum is σ = 21961280. Its totient is φ = 21345120.

The previous prime is 21652063. The next prime is 21652121. The reversal of 21652087 is 78025612.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21652087 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 (21650087) 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, 29173 + ... + 29905.

It is an arithmetic number, because the mean of its divisors is an integer number (2745160).

Almost surely, 2^21652087 is an apocalyptic number.

21652087 is a deficient number, since it is larger than the sum of its proper divisors (309193).

21652087 is a wasteful number, since it uses less digits than its factorization.

21652087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1113.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 21652087 is about 4653.1803102824. The cubic root of 21652087 is about 278.7190081305.

Adding to 21652087 its reverse (78025612), we get a palindrome (99677699).

The spelling of 21652087 in words is "twenty-one million, six hundred fifty-two thousand, eighty-seven".