21771632 has 20 divisors (see below), whose sum is σ = 42875976. Its totient is φ = 10706880.

The previous prime is 21771619. The next prime is 21771671. The reversal of 21771632 is 23617712.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21771595 and 21771604.

It is a congruent number.

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, 10178 + ... + 12129.

Almost surely, 2^21771632 is an apocalyptic number.

It is an amenable number.

21771632 is a deficient number, since it is larger than the sum of its proper divisors (21104344).

21771632 is a wasteful number, since it uses less digits than its factorization.

21771632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22376 (or 22370 counting only the distinct ones).

The product of its digits is 3528, while the sum is 29.

The square root of 21771632 is about 4666.0081440135. The cubic root of 21771632 is about 279.2310192874.

The spelling of 21771632 in words is "twenty-one million, seven hundred seventy-one thousand, six hundred thirty-two".