21541158912 has 456 divisors, whose sum is σ = 73635060576. Its totient is φ = 5549064192.

The previous prime is 21541158911. The next prime is 21541158913. The reversal of 21541158912 is 21985114512.

It is an interprime number because it is at equal distance from previous prime (21541158911) and next prime (21541158913).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21541158911) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 500957163 + ... + 500957205.

It is an arithmetic number, because the mean of its divisors is an integer number (161480396).

Almost surely, 2^21541158912 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 21541158912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36817530288).

21541158912 is an abundant number, since it is smaller than the sum of its proper divisors (52093901664).

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

21541158912 is an frugal number, since it uses more digits than its factorization.

21541158912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109 (or 68 counting only the distinct ones).

The product of its digits is 28800, while the sum is 39.

The spelling of 21541158912 in words is "twenty-one billion, five hundred forty-one million, one hundred fifty-eight thousand, nine hundred twelve".