21170110 has 16 divisors (see below), whose sum is σ = 41037696. Its totient is φ = 7816608.

The previous prime is 21170101. The next prime is 21170113. The reversal of 21170110 is 1107112.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21170113) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 81294 + ... + 81553.

It is an arithmetic number, because the mean of its divisors is an integer number (2564856).

Almost surely, 2^21170110 is an apocalyptic number.

21170110 is a deficient number, since it is larger than the sum of its proper divisors (19867586).

21170110 is a wasteful number, since it uses less digits than its factorization.

21170110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162867.

The product of its (nonzero) digits is 14, while the sum is 13.

The square root of 21170110 is about 4601.0987818129. The cubic root of 21170110 is about 276.6353684696.

Adding to 21170110 its reverse (1107112), we get a palindrome (22277222).

The spelling of 21170110 in words is "twenty-one million, one hundred seventy thousand, one hundred ten".