21120240000 has 160 divisors (see below), whose sum is σ = 70104153240. Its totient is φ = 5632000000.

The previous prime is 21120239977. The next prime is 21120240013. The reversal of 21120240000 is 4202112.

It is a tau number, because it is divible by the number of its divisors (160).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 196000 + ... + 284000.

Almost surely, 2^21120240000 is an apocalyptic number.

21120240000 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 21120240000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35052076620).

21120240000 is an abundant number, since it is smaller than the sum of its proper divisors (48983913240).

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

21120240000 is an frugal number, since it uses more digits than its factorization.

21120240000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88038 (or 88011 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21120240000 its reverse (4202112), we get a palindrome (21124442112).

The spelling of 21120240000 in words is "twenty-one billion, one hundred twenty million, two hundred forty thousand".