21052099 has 8 divisors (see below), whose sum is σ = 21572928. Its totient is φ = 20534400.

The previous prime is 21052091. The next prime is 21052111. The reversal of 21052099 is 99025012.

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 21052099 - 2³ = 21052091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21052091) 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, 18289 + ... + 19405.

It is an arithmetic number, because the mean of its divisors is an integer number (2696616).

Almost surely, 2^21052099 is an apocalyptic number.

21052099 is a deficient number, since it is larger than the sum of its proper divisors (520829).

21052099 is a wasteful number, since it uses less digits than its factorization.

21052099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1565.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 21052099 is about 4588.2566405989. The cubic root of 21052099 is about 276.1203834923.

The spelling of 21052099 in words is "twenty-one million, fifty-two thousand, ninety-nine".