21723068 has 6 divisors (see below), whose sum is σ = 38015376. Its totient is φ = 10861532.

The previous prime is 21723067. The next prime is 21723073. The reversal of 21723068 is 86032712.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21723068.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21723067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2715380 + ... + 2715387.

It is an arithmetic number, because the mean of its divisors is an integer number (6335896).

Almost surely, 2^21723068 is an apocalyptic number.

It is an amenable number.

21723068 is a deficient number, since it is larger than the sum of its proper divisors (16292308).

21723068 is a wasteful number, since it uses less digits than its factorization.

21723068 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5430771 (or 5430769 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 21723068 is about 4660.8012186747. The cubic root of 21723068 is about 279.0232463084.

The spelling of 21723068 in words is "twenty-one million, seven hundred twenty-three thousand, sixty-eight".