21055288 has 16 divisors (see below), whose sum is σ = 39611880. Its totient is φ = 10492128.

The previous prime is 21055277. The next prime is 21055291. The reversal of 21055288 is 88255012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1831 + ... + 6742.

Almost surely, 2^21055288 is an apocalyptic number.

It is an amenable number.

21055288 is a deficient number, since it is larger than the sum of its proper divisors (18556592).

21055288 is a wasteful number, since it uses less digits than its factorization.

21055288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8886 (or 8882 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 31.

The square root of 21055288 is about 4588.6041450533. The cubic root of 21055288 is about 276.1343251495.

The spelling of 21055288 in words is "twenty-one million, fifty-five thousand, two hundred eighty-eight".