21753120 has 48 divisors (see below), whose sum is σ = 68523840. Its totient is φ = 5800704.

The previous prime is 21753107. The next prime is 21753131. The reversal of 21753120 is 2135712.

It is a tau number, because it is divible by the number of its divisors (48).

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, 22180 + ... + 23139.

It is an arithmetic number, because the mean of its divisors is an integer number (1427580).

Almost surely, 2^21753120 is an apocalyptic number.

21753120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21753120 is an abundant number, since it is smaller than the sum of its proper divisors (46770720).

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

21753120 is a wasteful number, since it uses less digits than its factorization.

21753120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45337 (or 45329 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 21753120 is about 4664.0240136603. The cubic root of 21753120 is about 279.1518552574.

Adding to 21753120 its reverse (2135712), we get a palindrome (23888832).

The spelling of 21753120 in words is "twenty-one million, seven hundred fifty-three thousand, one hundred twenty".