21170106 has 32 divisors (see below), whose sum is σ = 47234880. Its totient is φ = 7028208.

The previous prime is 21170101. The next prime is 21170113. The reversal of 21170106 is 60107112.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21170101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15940 + ... + 17216.

It is an arithmetic number, because the mean of its divisors is an integer number (1476090).

Almost surely, 2^21170106 is an apocalyptic number.

21170106 is an abundant number, since it is smaller than the sum of its proper divisors (26064774).

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

21170106 is a wasteful number, since it uses less digits than its factorization.

21170106 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1595 (or 1589 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 18.

The square root of 21170106 is about 4601.0983471341. The cubic root of 21170106 is about 276.6353510466.

Adding to 21170106 its reverse (60107112), we get a palindrome (81277218).

The spelling of 21170106 in words is "twenty-one million, one hundred seventy thousand, one hundred six".