21768276 has 12 divisors (see below), whose sum is σ = 50792672. Its totient is φ = 7256088.

The previous prime is 21768269. The next prime is 21768289. The reversal of 21768276 is 67286712.

It is a tau number, because it is divible by the number of its divisors (12).

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, 907000 + ... + 907023.

Almost surely, 2^21768276 is an apocalyptic number.

It is an amenable number.

21768276 is an abundant number, since it is smaller than the sum of its proper divisors (29024396).

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

21768276 is a wasteful number, since it uses less digits than its factorization.

21768276 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1814030 (or 1814028 counting only the distinct ones).

The product of its digits is 56448, while the sum is 39.

The square root of 21768276 is about 4665.6485079783. The cubic root of 21768276 is about 279.2166711446.

The spelling of 21768276 in words is "twenty-one million, seven hundred sixty-eight thousand, two hundred seventy-six".