21386064 has 40 divisors (see below), whose sum is σ = 63140800. Its totient is φ = 6110208.

The previous prime is 21386047. The next prime is 21386117. The reversal of 21386064 is 46068312.

It is a congruent number.

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, 31489 + ... + 32160.

It is an arithmetic number, because the mean of its divisors is an integer number (1578520).

Almost surely, 2^21386064 is an apocalyptic number.

21386064 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21386064 is an abundant number, since it is smaller than the sum of its proper divisors (41754736).

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

21386064 is a wasteful number, since it uses less digits than its factorization.

21386064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63667 (or 63661 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 21386064 is about 4624.5068926319. The cubic root of 21386064 is about 277.5728304902.

The spelling of 21386064 in words is "twenty-one million, three hundred eighty-six thousand, sixty-four".