21072210216 has 32 divisors (see below), whose sum is σ = 53674500960. Its totient is φ = 6891540032.

The previous prime is 21072210199. The next prime is 21072210217. The reversal of 21072210216 is 61201227012.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (21072210217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8281830 + ... + 8284373.

It is an arithmetic number, because the mean of its divisors is an integer number (1677328155).

Almost surely, 2^21072210216 is an apocalyptic number.

It is an amenable number.

21072210216 is an abundant number, since it is smaller than the sum of its proper divisors (32602290744).

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

21072210216 is a wasteful number, since it uses less digits than its factorization.

21072210216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16566265 (or 16566261 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

Adding to 21072210216 its reverse (61201227012), we get a palindrome (82273437228).

The spelling of 21072210216 in words is "twenty-one billion, seventy-two million, two hundred ten thousand, two hundred sixteen".