21704360 has 32 divisors (see below), whose sum is σ = 49510440. Its totient is φ = 8561664.

The previous prime is 21704357. The next prime is 21704369. The reversal of 21704360 is 6340712.

It can be written as a sum of positive squares in 4 ways, for example, as 12716356 + 8988004 = 3566^2 + 2998^2 .

It is not an unprimeable number, because it can be changed into a prime (21704369) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 797 + ... + 6636.

Almost surely, 2^21704360 is an apocalyptic number.

21704360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21704360 is an abundant number, since it is smaller than the sum of its proper divisors (27806080).

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

21704360 is a wasteful number, since it uses less digits than its factorization.

21704360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7517 (or 7513 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 21704360 is about 4658.7938353183. The cubic root of 21704360 is about 278.9431246286.

The spelling of 21704360 in words is "twenty-one million, seven hundred four thousand, three hundred sixty".