21771652 has 24 divisors (see below), whose sum is σ = 43775424. Its totient is φ = 9280992.

The previous prime is 21771619. The next prime is 21771671. The reversal of 21771652 is 25617712.

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, 3543 + ... + 7489.

It is an arithmetic number, because the mean of its divisors is an integer number (1823976).

Almost surely, 2^21771652 is an apocalyptic number.

It is an amenable number.

21771652 is an abundant number, since it is smaller than the sum of its proper divisors (22003772).

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

21771652 is a wasteful number, since it uses less digits than its factorization.

21771652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4155 (or 4153 counting only the distinct ones).

The product of its digits is 5880, while the sum is 31.

The square root of 21771652 is about 4666.0102871725. The cubic root of 21771652 is about 279.2311047904.

The spelling of 21771652 in words is "twenty-one million, seven hundred seventy-one thousand, six hundred fifty-two".