21099594 has 8 divisors (see below), whose sum is σ = 42199200. Its totient is φ = 7033196.

The previous prime is 21099593. The next prime is 21099613. The reversal of 21099594 is 49599012.

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

21099594 is an admirable number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21099593) 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 3 ways as a sum of consecutive naturals, for example, 1758294 + ... + 1758305.

It is an arithmetic number, because the mean of its divisors is an integer number (5274900).

Almost surely, 2^21099594 is an apocalyptic number.

21099594 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21099594 is a wasteful number, since it uses less digits than its factorization.

21099594 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3516604.

The product of its (nonzero) digits is 29160, while the sum is 39.

The square root of 21099594 is about 4593.4294377948. The cubic root of 21099594 is about 276.3278764628.

The spelling of 21099594 in words is "twenty-one million, ninety-nine thousand, five hundred ninety-four".