21163001216 has 64 divisors (see below), whose sum is σ = 49167060000. Its totient is φ = 9069838848.

The previous prime is 21163001213. The next prime is 21163001219. The reversal of 21163001216 is 61210036112.

It is an interprime number because it is at equal distance from previous prime (21163001213) and next prime (21163001219).

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 21163001191 and 21163001200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21163001213) 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, 197111 + ... + 284918.

Almost surely, 2^21163001216 is an apocalyptic number.

It is an amenable number.

21163001216 is an abundant number, since it is smaller than the sum of its proper divisors (28004058784).

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

21163001216 is an frugal number, since it uses more digits than its factorization.

21163001216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 482064 (or 482038 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 23.

Adding to 21163001216 its reverse (61210036112), we get a palindrome (82373037328).

The spelling of 21163001216 in words is "twenty-one billion, one hundred sixty-three million, one thousand, two hundred sixteen".