21473764 has 24 divisors (see below), whose sum is σ = 41567288. Its totient is φ = 9642240.

The previous prime is 21473747. The next prime is 21473773. The reversal of 21473764 is 46737412.

It can be written as a sum of positive squares in 4 ways, for example, as 240100 + 21233664 = 490^2 + 4608^2 .

It is a super-2 number, since 2×21473764² = 922245080655392, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3657 + ... + 7504.

Almost surely, 2^21473764 is an apocalyptic number.

It is an amenable number.

21473764 is a deficient number, since it is larger than the sum of its proper divisors (20093524).

21473764 is a wasteful number, since it uses less digits than its factorization.

21473764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11215 (or 11213 counting only the distinct ones).

The product of its digits is 28224, while the sum is 34.

The square root of 21473764 is about 4633.9792835100. The cubic root of 21473764 is about 277.9517367003.

The spelling of 21473764 in words is "twenty-one million, four hundred seventy-three thousand, seven hundred sixty-four".