21768484 has 6 divisors (see below), whose sum is σ = 38094854. Its totient is φ = 10884240.

The previous prime is 21768457. The next prime is 21768497. The reversal of 21768484 is 48486712.

It can be written as a sum of positive squares in only one way, i.e., 11075584 + 10692900 = 3328^2 + 3270^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2721057 + ... + 2721064.

Almost surely, 2^21768484 is an apocalyptic number.

It is an amenable number.

21768484 is a deficient number, since it is larger than the sum of its proper divisors (16326370).

21768484 is a wasteful number, since it uses less digits than its factorization.

21768484 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5442125 (or 5442123 counting only the distinct ones).

The product of its digits is 86016, while the sum is 40.

The square root of 21768484 is about 4665.6707985026. The cubic root of 21768484 is about 279.2175604645.

The spelling of 21768484 in words is "twenty-one million, seven hundred sixty-eight thousand, four hundred eighty-four".