21915106 has 8 divisors (see below), whose sum is σ = 32967900. Its totient is φ = 10925808.

The previous prime is 21915077. The next prime is 21915119. The reversal of 21915106 is 60151912.

It can be written as a sum of positive squares in 2 ways, for example, as 21762225 + 152881 = 4665^2 + 391^2 .

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

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 15001 + ... + 16396.

Almost surely, 2^21915106 is an apocalyptic number.

21915106 is a deficient number, since it is larger than the sum of its proper divisors (11052794).

21915106 is a wasteful number, since it uses less digits than its factorization.

21915106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31748.

The product of its (nonzero) digits is 540, while the sum is 25.

The square root of 21915106 is about 4681.3572818148. The cubic root of 21915106 is about 279.8430497952.

The spelling of 21915106 in words is "twenty-one million, nine hundred fifteen thousand, one hundred six".