21921095 has 8 divisors (see below), whose sum is σ = 30063264. Its totient is φ = 15031584.

The previous prime is 21921083. The next prime is 21921113. The reversal of 21921095 is 59012912.

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-21921095 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 313124 + ... + 313193.

It is an arithmetic number, because the mean of its divisors is an integer number (3757908).

Almost surely, 2^21921095 is an apocalyptic number.

21921095 is a deficient number, since it is larger than the sum of its proper divisors (8142169).

21921095 is an equidigital number, since it uses as much as digits as its factorization.

21921095 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626329.

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 21921095 is about 4681.9969030319. The cubic root of 21921095 is about 279.8685394792.

Adding to 21921095 its sum of digits (29), we get a square (21921124 = 4682²).

The spelling of 21921095 in words is "twenty-one million, nine hundred twenty-one thousand, ninety-five".