21969748 has 12 divisors (see below), whose sum is σ = 38741472. Its totient is φ = 10900760.

The previous prime is 21969709. The next prime is 21969781. The reversal of 21969748 is 84796912.

It is a junction number, because it is equal to n+sod(n) for n = 21969698 and 21969707.

It is a congruent number.

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, 20440 + ... + 21487.

It is an arithmetic number, because the mean of its divisors is an integer number (3228456).

Almost surely, 2^21969748 is an apocalyptic number.

It is an amenable number.

21969748 is a deficient number, since it is larger than the sum of its proper divisors (16771724).

21969748 is a wasteful number, since it uses less digits than its factorization.

21969748 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42062 (or 42060 counting only the distinct ones).

The product of its digits is 217728, while the sum is 46.

The square root of 21969748 is about 4687.1897764012. The cubic root of 21969748 is about 280.0754388568.

The spelling of 21969748 in words is "twenty-one million, nine hundred sixty-nine thousand, seven hundred forty-eight".