21770764 has 24 divisors (see below), whose sum is σ = 40093200. Its totient is φ = 10328640.

The previous prime is 21770747. The next prime is 21770797. The reversal of 21770764 is 46707712.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5254 + ... + 8434.

It is an arithmetic number, because the mean of its divisors is an integer number (1670550).

Almost surely, 2^21770764 is an apocalyptic number.

It is an amenable number.

21770764 is a deficient number, since it is larger than the sum of its proper divisors (18322436).

21770764 is a wasteful number, since it uses less digits than its factorization.

21770764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3273 (or 3271 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 34.

The square root of 21770764 is about 4665.9151299611. The cubic root of 21770764 is about 279.2273084073.

The spelling of 21770764 in words is "twenty-one million, seven hundred seventy thousand, seven hundred sixty-four".