21512663040000 has 1280 divisors, whose sum is σ = 79108189776000. Its totient is φ = 5155061760000.

The previous prime is 21512663039981. The next prime is 21512663040007. The reversal of 21512663040000 is 4036621512.

It is a tau number, because it is divible by the number of its divisors (1280).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a self number, because there is not a number n which added to its sum of digits gives 21512663040000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21512663040007) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 93941759886 + ... + 93941760114.

Almost surely, 2^{21512663040000} is an apocalyptic number.

21512663040000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21512663040000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39554094888000).

21512663040000 is an abundant number, since it is smaller than the sum of its proper divisors (57595526736000).

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

21512663040000 is an equidigital number, since it uses as much as digits as its factorization.

21512663040000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432 (or 389 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

Adding to 21512663040000 its reverse (4036621512), we get a palindrome (21516699661512).

The spelling of 21512663040000 in words is "twenty-one trillion, five hundred twelve billion, six hundred sixty-three million, forty thousand".