21170120 has 32 divisors (see below), whose sum is σ = 49705920. Its totient is φ = 8099520.

The previous prime is 21170119. The next prime is 21170131. The reversal of 21170120 is 2107112.

It is a junction number, because it is equal to n+sod(n) for n = 21170095 and 21170104.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10586 + ... + 12425.

It is an arithmetic number, because the mean of its divisors is an integer number (1553310).

Almost surely, 2^21170120 is an apocalyptic number.

21170120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21170120 is an abundant number, since it is smaller than the sum of its proper divisors (28535800).

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

21170120 is a wasteful number, since it uses less digits than its factorization.

21170120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23045 (or 23041 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 14.

The square root of 21170120 is about 4601.0998685097. The cubic root of 21170120 is about 276.6354120272.

Adding to 21170120 its reverse (2107112), we get a palindrome (23277232).

The spelling of 21170120 in words is "twenty-one million, one hundred seventy thousand, one hundred twenty".