21652091 has 8 divisors (see below), whose sum is σ = 22278960. Its totient is φ = 21030912.

The previous prime is 21652063. The next prime is 21652121. The reversal of 21652091 is 19025612.

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 21652091 - 2²² = 17457787 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 21652091.

It is not an unprimeable number, because it can be changed into a prime (21652061) 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, 6995 + ... + 9603.

It is an arithmetic number, because the mean of its divisors is an integer number (2784870).

Almost surely, 2^21652091 is an apocalyptic number.

21652091 is a deficient number, since it is larger than the sum of its proper divisors (626869).

21652091 is a wasteful number, since it uses less digits than its factorization.

21652091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2845.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 21652091 is about 4653.1807400960. The cubic root of 21652091 is about 278.7190252940.

The spelling of 21652091 in words is "twenty-one million, six hundred fifty-two thousand, ninety-one".