21111450360 has 256 divisors, whose sum is σ = 85036815360. Its totient is φ = 4049326080.

The previous prime is 21111450331. The next prime is 21111450383. The reversal of 21111450360 is 6305411112.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21111450360.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 32244 + ... + 207996.

It is an arithmetic number, because the mean of its divisors is an integer number (332175060).

Almost surely, 2^21111450360 is an apocalyptic number.

21111450360 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 21111450360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42518407680).

21111450360 is an abundant number, since it is smaller than the sum of its proper divisors (63925365000).

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

21111450360 is a wasteful number, since it uses less digits than its factorization.

21111450360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175798 (or 175794 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 24.

Adding to 21111450360 its reverse (6305411112), we get a palindrome (27416861472).

The spelling of 21111450360 in words is "twenty-one billion, one hundred eleven million, four hundred fifty thousand, three hundred sixty".