21065704 has 16 divisors (see below), whose sum is σ = 43089120. Its totient is φ = 9575280.

The previous prime is 21065701. The next prime is 21065711. The reversal of 21065704 is 40756012.

It is not an unprimeable number, because it can be changed into a prime (21065701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 119604 + ... + 119779.

It is an arithmetic number, because the mean of its divisors is an integer number (2693070).

Almost surely, 2^21065704 is an apocalyptic number.

It is an amenable number.

21065704 is an abundant number, since it is smaller than the sum of its proper divisors (22023416).

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

21065704 is a wasteful number, since it uses less digits than its factorization.

21065704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239400 (or 239396 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 21065704 is about 4589.7389904002. The cubic root of 21065704 is about 276.1798519704.

The spelling of 21065704 in words is "twenty-one million, sixty-five thousand, seven hundred four".