21310511616 has 400 divisors, whose sum is σ = 66379376448. Its totient is φ = 6801408000.

The previous prime is 21310511611. The next prime is 21310511617. The reversal of 21310511616 is 61611501312.

21310511616 is a `hidden beast` number, since 2 + 1 + 31 + 0 + 5 + 11 + 616 = 666.

It is a super-3 number, since 3×21310511616³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 21310511616.

It is not an unprimeable number, because it can be changed into a prime (21310511611) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 141129141 + ... + 141129291.

Almost surely, 2^21310511616 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21310511616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33189688224).

21310511616 is an abundant number, since it is smaller than the sum of its proper divisors (45068864832).

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

21310511616 is an equidigital number, since it uses as much as digits as its factorization.

21310511616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305 (or 280 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The spelling of 21310511616 in words is "twenty-one billion, three hundred ten million, five hundred eleven thousand, six hundred sixteen".