21703940 has 12 divisors (see below), whose sum is σ = 45578316. Its totient is φ = 8681568.

The previous prime is 21703897. The next prime is 21703967. The reversal of 21703940 is 4930712.

It can be written as a sum of positive squares in 2 ways, for example, as 5317636 + 16386304 = 2306^2 + 4048^2 .

It is a super-2 number, since 2×21703940² = 942122023047200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 542579 + ... + 542618.

It is an arithmetic number, because the mean of its divisors is an integer number (3798193).

Almost surely, 2^21703940 is an apocalyptic number.

21703940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21703940 is an abundant number, since it is smaller than the sum of its proper divisors (23874376).

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

21703940 is a wasteful number, since it uses less digits than its factorization.

21703940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1085206 (or 1085204 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 21703940 is about 4658.7487590554. The cubic root of 21703940 is about 278.9413253455.

The spelling of 21703940 in words is "twenty-one million, seven hundred three thousand, nine hundred forty".