21740712 has 128 divisors (see below), whose sum is σ = 67200000. Its totient is φ = 5842368.

The previous prime is 21740711. The next prime is 21740717. The reversal of 21740712 is 21704712.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (21740711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 156339 + ... + 156477.

It is an arithmetic number, because the mean of its divisors is an integer number (525000).

Almost surely, 2^21740712 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21740712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33600000).

21740712 is an abundant number, since it is smaller than the sum of its proper divisors (45459288).

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

21740712 is a wasteful number, since it uses less digits than its factorization.

21740712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188 (or 170 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 24.

The square root of 21740712 is about 4662.6936420914. The cubic root of 21740712 is about 279.0987690028.

The spelling of 21740712 in words is "twenty-one million, seven hundred forty thousand, seven hundred twelve".