21143120240 has 80 divisors (see below), whose sum is σ = 53826599520. Its totient is φ = 7659740160.

The previous prime is 21143120209. The next prime is 21143120311. The reversal of 21143120240 is 4202134112.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 192062 + ... + 281378.

It is an arithmetic number, because the mean of its divisors is an integer number (672832494).

Almost surely, 2^21143120240 is an apocalyptic number.

21143120240 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 21143120240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26913299760).

21143120240 is an abundant number, since it is smaller than the sum of its proper divisors (32683479280).

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

21143120240 is a wasteful number, since it uses less digits than its factorization.

21143120240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89610 (or 89604 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21143120240 its reverse (4202134112), we get a palindrome (25345254352).

The spelling of 21143120240 in words is "twenty-one billion, one hundred forty-three million, one hundred twenty thousand, two hundred forty".