21772648 has 16 divisors (see below), whose sum is σ = 43225380. Its totient is φ = 10245888.

The previous prime is 21772607. The next prime is 21772691. The reversal of 21772648 is 84627712.

It can be written as a sum of positive squares in 2 ways, for example, as 20994724 + 777924 = 4582^2 + 882^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 79911 + ... + 80182.

Almost surely, 2^21772648 is an apocalyptic number.

It is an amenable number.

21772648 is a deficient number, since it is larger than the sum of its proper divisors (21452732).

21772648 is a wasteful number, since it uses less digits than its factorization.

21772648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160116 (or 160112 counting only the distinct ones).

The product of its digits is 37632, while the sum is 37.

The square root of 21772648 is about 4666.1170152494. The cubic root of 21772648 is about 279.2353627729.

The spelling of 21772648 in words is "twenty-one million, seven hundred seventy-two thousand, six hundred forty-eight".