21370680 has 192 divisors, whose sum is σ = 75816000. Its totient is φ = 5203968.

The previous prime is 21370667. The next prime is 21370681. The reversal of 21370680 is 8607312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21370681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 240076 + ... + 240164.

It is an arithmetic number, because the mean of its divisors is an integer number (394875).

Almost surely, 2^21370680 is an apocalyptic number.

21370680 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 21370680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37908000).

21370680 is an abundant number, since it is smaller than the sum of its proper divisors (54445320).

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

21370680 is a wasteful number, since it uses less digits than its factorization.

21370680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 21370680 is about 4622.8432809257. The cubic root of 21370680 is about 277.5062574679.

Adding to 21370680 its reverse (8607312), we get a palindrome (29977992).

The spelling of 21370680 in words is "twenty-one million, three hundred seventy thousand, six hundred eighty".