21755084 has 24 divisors (see below), whose sum is σ = 41136480. Its totient is φ = 10007424.

The previous prime is 21755077. The next prime is 21755089. The reversal of 21755084 is 48055712.

It is a self number, because there is not a number n which added to its sum of digits gives 21755084.

It is not an unprimeable number, because it can be changed into a prime (21755089) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22352 + ... + 23304.

It is an arithmetic number, because the mean of its divisors is an integer number (1714020).

Almost surely, 2^21755084 is an apocalyptic number.

It is an amenable number.

21755084 is a deficient number, since it is larger than the sum of its proper divisors (19381396).

21755084 is a wasteful number, since it uses less digits than its factorization.

21755084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1409 (or 1407 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 32.

The square root of 21755084 is about 4664.2345567092. The cubic root of 21755084 is about 279.1602561633.

The spelling of 21755084 in words is "twenty-one million, seven hundred fifty-five thousand, eighty-four".