21513511505000 has 40 divisors (see below), whose sum is σ = 50406157467930. Its totient is φ = 8605404600000.

The previous prime is 21513511504981. The next prime is 21513511505011. The reversal of 21513511505000 is 50511531512.

It can be written as a sum of positive squares in 5 ways, for example, as 2083594093156 + 19429917411844 = 1443466^2 + 4407938^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 2151346151 + ... + 2151356150.

Almost surely, 2^{21513511505000} is an apocalyptic number.

21513511505000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21513511505000 is an abundant number, since it is smaller than the sum of its proper divisors (28892645962930).

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

21513511505000 is an equidigital number, since it uses as much as digits as its factorization.

21513511505000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4302702327 (or 4302702308 counting only the distinct ones).

The product of its (nonzero) digits is 3750, while the sum is 29.

The spelling of 21513511505000 in words is "twenty-one trillion, five hundred thirteen billion, five hundred eleven million, five hundred five thousand".