21511040000000 has 896 divisors, whose sum is σ = 59516214825600. Its totient is φ = 7741440000000.

The previous prime is 21511039999987. The next prime is 21511040000011. The reversal of 21511040000000 is 4011512.

It is a self number, because there is not a number n which added to its sum of digits gives 21511040000000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 352639999970 + ... + 352640000030.

Almost surely, 2^{21511040000000} is an apocalyptic number.

21511040000000 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 21511040000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29758107412800).

21511040000000 is an abundant number, since it is smaller than the sum of its proper divisors (38005174825600).

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

21511040000000 is an frugal number, since it uses more digits than its factorization.

21511040000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170 (or 116 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 14.

Adding to 21511040000000 its reverse (4011512), we get a palindrome (21511044011512).

The spelling of 21511040000000 in words is "twenty-one trillion, five hundred eleven billion, forty million", and thus it is an aban number.