21106654 has 4 divisors (see below), whose sum is σ = 31659984. Its totient is φ = 10553326.

The previous prime is 21106643. The next prime is 21106661. The reversal of 21106654 is 45660112.

It is a semiprime because it is the product of two primes.

It is a congruent number.

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 as a sum of consecutive naturals, namely, 5276662 + ... + 5276665.

It is an arithmetic number, because the mean of its divisors is an integer number (7914996).

Almost surely, 2^21106654 is an apocalyptic number.

21106654 is a deficient number, since it is larger than the sum of its proper divisors (10553330).

21106654 is a wasteful number, since it uses less digits than its factorization.

21106654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10553329.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 21106654 is about 4594.1978625218. The cubic root of 21106654 is about 276.3586931262.

Adding to 21106654 its reverse (45660112), we get a palindrome (66766766).

The spelling of 21106654 in words is "twenty-one million, one hundred six thousand, six hundred fifty-four".