21505541135012 has 24 divisors (see below), whose sum is σ = 41058532845792. Its totient is φ = 9774650787200.

The previous prime is 21505541134981. The next prime is 21505541135051. The reversal of 21505541135012 is 21053114550512.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14148314 + ... + 15594417.

It is an arithmetic number, because the mean of its divisors is an integer number (1710772201908).

Almost surely, 2^{21505541135012} is an apocalyptic number.

21505541135012 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21505541135012 is a deficient number, since it is larger than the sum of its proper divisors (19552991710780).

21505541135012 is a wasteful number, since it uses less digits than its factorization.

21505541135012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29759179 (or 29759177 counting only the distinct ones).

The product of its (nonzero) digits is 30000, while the sum is 35.

Adding to 21505541135012 its reverse (21053114550512), we get a palindrome (42558655685524).

The spelling of 21505541135012 in words is "twenty-one trillion, five hundred five billion, five hundred forty-one million, one hundred thirty-five thousand, twelve".