21413560 has 64 divisors (see below), whose sum is σ = 56862720. Its totient is φ = 7102080.

The previous prime is 21413549. The next prime is 21413569. The reversal of 21413560 is 6531412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21413569) 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, 7447 + ... + 9913.

It is an arithmetic number, because the mean of its divisors is an integer number (888480).

Almost surely, 2^21413560 is an apocalyptic number.

21413560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21413560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28431360).

21413560 is an abundant number, since it is smaller than the sum of its proper divisors (35449160).

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

21413560 is a wasteful number, since it uses less digits than its factorization.

21413560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2516 (or 2512 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 21413560 is about 4627.4787951972. The cubic root of 21413560 is about 277.6917377375.

Adding to 21413560 its reverse (6531412), we get a palindrome (27944972).

The spelling of 21413560 in words is "twenty-one million, four hundred thirteen thousand, five hundred sixty".