21423121140 has 24 divisors (see below), whose sum is σ = 59984739360. Its totient is φ = 5712832288.

The previous prime is 21423121123. The next prime is 21423121147. The reversal of 21423121140 is 4112132412.

It is a super-2 number, since 2×21423121140² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21423121147) 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, 178525950 + ... + 178526069.

It is an arithmetic number, because the mean of its divisors is an integer number (2499364140).

Almost surely, 2^21423121140 is an apocalyptic number.

21423121140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21423121140 is an abundant number, since it is smaller than the sum of its proper divisors (38561618220).

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

21423121140 is a wasteful number, since it uses less digits than its factorization.

21423121140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357052031 (or 357052029 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

Adding to 21423121140 its reverse (4112132412), we get a palindrome (25535253552).

The spelling of 21423121140 in words is "twenty-one billion, four hundred twenty-three million, one hundred twenty-one thousand, one hundred forty".