21723702 has 64 divisors (see below), whose sum is σ = 58351104. Its totient is φ = 5207040.

The previous prime is 21723701. The next prime is 21723719. The reversal of 21723702 is 20732712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21723701) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4198 + ... + 7814.

It is an arithmetic number, because the mean of its divisors is an integer number (911736).

Almost surely, 2^21723702 is an apocalyptic number.

21723702 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21723702, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29175552).

21723702 is an abundant number, since it is smaller than the sum of its proper divisors (36627402).

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

21723702 is a wasteful number, since it uses less digits than its factorization.

21723702 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3653.

The product of its (nonzero) digits is 1176, while the sum is 24.

The square root of 21723702 is about 4660.8692322355. The cubic root of 21723702 is about 279.0259607656.

The spelling of 21723702 in words is "twenty-one million, seven hundred twenty-three thousand, seven hundred two".