21423144140 has 24 divisors (see below), whose sum is σ = 45660077232. Its totient is φ = 8441357760.

The previous prime is 21423144109. The next prime is 21423144143. The reversal of 21423144140 is 4144132412.

It is a super-3 number, since 3×21423144140³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (21423144143) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7992371 + ... + 7995050.

It is an arithmetic number, because the mean of its divisors is an integer number (1902503218).

Almost surely, 2^21423144140 is an apocalyptic number.

21423144140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21423144140 is an abundant number, since it is smaller than the sum of its proper divisors (24236933092).

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

21423144140 is a wasteful number, since it uses less digits than its factorization.

21423144140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15987497 (or 15987495 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 26.

Adding to 21423144140 its reverse (4144132412), we get a palindrome (25567276552).

The spelling of 21423144140 in words is "twenty-one billion, four hundred twenty-three million, one hundred forty-four thousand, one hundred forty".