21003223216 has 40 divisors (see below), whose sum is σ = 41155691760. Its totient is φ = 10382862336.

The previous prime is 21003223211. The next prime is 21003223229. The reversal of 21003223216 is 61232230012.

It is a super-2 number, since 2×21003223216² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21003223211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 725271 + ... + 753673.

It is an arithmetic number, because the mean of its divisors is an integer number (1028892294).

Almost surely, 2^21003223216 is an apocalyptic number.

It is an amenable number.

21003223216 is a deficient number, since it is larger than the sum of its proper divisors (20152468544).

21003223216 is a wasteful number, since it uses less digits than its factorization.

21003223216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28933 (or 28927 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 22.

Adding to 21003223216 its reverse (61232230012), we get a palindrome (82235453228).

The spelling of 21003223216 in words is "twenty-one billion, three million, two hundred twenty-three thousand, two hundred sixteen".