21170470512 has 20 divisors (see below), whose sum is σ = 54690382280. Its totient is φ = 7056823488.

The previous prime is 21170470507. The next prime is 21170470513. The reversal of 21170470512 is 21507407112.

It is a self number, because there is not a number n which added to its sum of digits gives 21170470512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21170470513) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 220525687 + ... + 220525782.

It is an arithmetic number, because the mean of its divisors is an integer number (2734519114).

Almost surely, 2^21170470512 is an apocalyptic number.

It is an amenable number.

21170470512 is an abundant number, since it is smaller than the sum of its proper divisors (33519911768).

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

21170470512 is a wasteful number, since it uses less digits than its factorization.

21170470512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441051480 (or 441051474 counting only the distinct ones).

The product of its (nonzero) digits is 3920, while the sum is 30.

Adding to 21170470512 its reverse (21507407112), we get a palindrome (42677877624).

The spelling of 21170470512 in words is "twenty-one billion, one hundred seventy million, four hundred seventy thousand, five hundred twelve".