21202454240 has 96 divisors (see below), whose sum is σ = 54712161504. Its totient is φ = 7700439040.

The previous prime is 21202454197. The next prime is 21202454249. The reversal of 21202454240 is 4245420212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202454249) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 1501292 + ... + 1515348.

It is an arithmetic number, because the mean of its divisors is an integer number (569918349).

Almost surely, 2^21202454240 is an apocalyptic number.

21202454240 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 21202454240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27356080752).

21202454240 is an abundant number, since it is smaller than the sum of its proper divisors (33509707264).

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

21202454240 is a wasteful number, since it uses less digits than its factorization.

21202454240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14940 (or 14932 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 26.

Adding to 21202454240 its reverse (4245420212), we get a palindrome (25447874452).

The spelling of 21202454240 in words is "twenty-one billion, two hundred two million, four hundred fifty-four thousand, two hundred forty".