21331205140 has 24 divisors (see below), whose sum is σ = 51194892672. Its totient is φ = 7313556000.

The previous prime is 21331205101. The next prime is 21331205143. The reversal of 21331205140 is 4150213312.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331205143) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 76182736 + ... + 76183015.

It is an arithmetic number, because the mean of its divisors is an integer number (2133120528).

Almost surely, 2^21331205140 is an apocalyptic number.

21331205140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21331205140 is an abundant number, since it is smaller than the sum of its proper divisors (29863687532).

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

21331205140 is a wasteful number, since it uses less digits than its factorization.

21331205140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152365767 (or 152365765 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

Adding to 21331205140 its reverse (4150213312), we get a palindrome (25481418452).

The spelling of 21331205140 in words is "twenty-one billion, three hundred thirty-one million, two hundred five thousand, one hundred forty".