21106610 has 32 divisors (see below), whose sum is σ = 44140032. Its totient is φ = 7116480.

The previous prime is 21106607. The next prime is 21106643. The reversal of 21106610 is 1660112.

It is a happy number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1799 + ... + 6741.

It is an arithmetic number, because the mean of its divisors is an integer number (1379376).

Almost surely, 2^21106610 is an apocalyptic number.

21106610 is an abundant number, since it is smaller than the sum of its proper divisors (23033422).

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

21106610 is a wasteful number, since it uses less digits than its factorization.

21106610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5018.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 21106610 is about 4594.1930738705. The cubic root of 21106610 is about 276.3585010889.

Adding to 21106610 its reverse (1660112), we get a palindrome (22766722).

The spelling of 21106610 in words is "twenty-one million, one hundred six thousand, six hundred ten".