21210270064 has 20 divisors (see below), whose sum is σ = 41099692120. Its totient is φ = 10603897920.

The previous prime is 21210270047. The next prime is 21210270079. The reversal of 21210270064 is 46007201212.

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, 72979 + ... + 218509.

It is an arithmetic number, because the mean of its divisors is an integer number (2054984606).

Almost surely, 2^21210270064 is an apocalyptic number.

It is an amenable number.

21210270064 is a deficient number, since it is larger than the sum of its proper divisors (19889422056).

21210270064 is a wasteful number, since it uses less digits than its factorization.

21210270064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154648 (or 154642 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 25.

Adding to 21210270064 its reverse (46007201212), we get a palindrome (67217471276).

The spelling of 21210270064 in words is "twenty-one billion, two hundred ten million, two hundred seventy thousand, sixty-four".