21734568 has 80 divisors (see below), whose sum is σ = 64490580. Its totient is φ = 6815232.

The previous prime is 21734527. The next prime is 21734593. The reversal of 21734568 is 86543712.

21734568 is a `hidden beast` number, since 21 + 73 + 4 + 568 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 21734244 + 324 = 4662^2 + 18^2 .

It is a super-2 number, since 2×21734568² = 944782892293248, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 10030 + ... + 12002.

Almost surely, 2^21734568 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 21734568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32245290).

21734568 is an abundant number, since it is smaller than the sum of its proper divisors (42756012).

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

21734568 is a wasteful number, since it uses less digits than its factorization.

21734568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2008 (or 1995 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 21734568 is about 4662.0347489052. The cubic root of 21734568 is about 279.0724751016.

The spelling of 21734568 in words is "twenty-one million, seven hundred thirty-four thousand, five hundred sixty-eight".