21723014 has 4 divisors (see below), whose sum is σ = 32584524. Its totient is φ = 10861506.

The previous prime is 21722999. The next prime is 21723019. The reversal of 21723014 is 41032712.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21723019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5430752 + ... + 5430755.

It is an arithmetic number, because the mean of its divisors is an integer number (8146131).

Almost surely, 2^21723014 is an apocalyptic number.

21723014 is a deficient number, since it is larger than the sum of its proper divisors (10861510).

21723014 is a wasteful number, since it uses less digits than its factorization.

21723014 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10861509.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21723014 is about 4660.7954256758. The cubic root of 21723014 is about 279.0230151061.

Adding to 21723014 its reverse (41032712), we get a palindrome (62755726).

The spelling of 21723014 in words is "twenty-one million, seven hundred twenty-three thousand, fourteen".