21859064 has 8 divisors (see below), whose sum is σ = 40985760. Its totient is φ = 10929528.

The previous prime is 21859049. The next prime is 21859067. The reversal of 21859064 is 46095812.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21859067) 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 as a sum of consecutive naturals, namely, 1366184 + ... + 1366199.

It is an arithmetic number, because the mean of its divisors is an integer number (5123220).

Almost surely, 2^21859064 is an apocalyptic number.

It is an amenable number.

21859064 is a deficient number, since it is larger than the sum of its proper divisors (19126696).

21859064 is a wasteful number, since it uses less digits than its factorization.

21859064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2732389 (or 2732385 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 21859064 is about 4675.3677930191. The cubic root of 21859064 is about 279.6043050143.

The spelling of 21859064 in words is "twenty-one million, eight hundred fifty-nine thousand, sixty-four".