21201120 has 72 divisors (see below), whose sum is σ = 72353736. Its totient is φ = 5653248.

The previous prime is 21201109. The next prime is 21201121. The reversal of 21201120 is 2110212.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201121) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5922 + ... + 8801.

It is an arithmetic number, because the mean of its divisors is an integer number (1004913).

Almost surely, 2^21201120 is an apocalyptic number.

21201120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201120 is an abundant number, since it is smaller than the sum of its proper divisors (51152616).

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

21201120 is a wasteful number, since it uses less digits than its factorization.

21201120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14744 (or 14733 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 21201120 is about 4604.4673959102. The cubic root of 21201120 is about 276.7703745009.

Adding to 21201120 its reverse (2110212), we get a palindrome (23311332).

It can be divided in two parts, 21201 and 120, that added together give a triangular number (21321 = T₂₀₆).

The spelling of 21201120 in words is "twenty-one million, two hundred one thousand, one hundred twenty".