21070064 has 20 divisors (see below), whose sum is σ = 41820240. Its totient is φ = 10277760.

The previous prime is 21070033. The next prime is 21070073. The reversal of 21070064 is 46007012.

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, 15404 + ... + 16715.

It is an arithmetic number, because the mean of its divisors is an integer number (2091012).

Almost surely, 2^21070064 is an apocalyptic number.

It is an amenable number.

21070064 is a deficient number, since it is larger than the sum of its proper divisors (20750176).

21070064 is a wasteful number, since it uses less digits than its factorization.

21070064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32168 (or 32162 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21070064 is about 4590.2139383693. The cubic root of 21070064 is about 276.1989044405.

Adding to 21070064 its reverse (46007012), we get a palindrome (67077076).

The spelling of 21070064 in words is "twenty-one million, seventy thousand, sixty-four".