21703716 has 36 divisors (see below), whose sum is σ = 56756700. Its totient is φ = 6984768.

The previous prime is 21703711. The next prime is 21703723. The reversal of 21703716 is 61730712.

It can be written as a sum of positive squares in 2 ways, for example, as 15681600 + 6022116 = 3960^2 + 2454^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 21703716.

It is not an unprimeable number, because it can be changed into a prime (21703711) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9351 + ... + 11438.

It is an arithmetic number, because the mean of its divisors is an integer number (1576575).

Almost surely, 2^21703716 is an apocalyptic number.

It is an amenable number.

21703716 is an abundant number, since it is smaller than the sum of its proper divisors (35052984).

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

21703716 is a wasteful number, since it uses less digits than its factorization.

21703716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20828 (or 20823 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 27.

The square root of 21703716 is about 4658.7247182035. The cubic root of 21703716 is about 278.9403657183.

It can be divided in two parts, 2170 and 3716, that added together give a triangular number (5886 = T₁₀₈).

The spelling of 21703716 in words is "twenty-one million, seven hundred three thousand, seven hundred sixteen".