21442145135140 has 24 divisors (see below), whose sum is σ = 45030679159032. Its totient is φ = 8576443887360.

The previous prime is 21442145135113. The next prime is 21442145135149. The reversal of 21442145135140 is 4153154124412.

It can be written as a sum of positive squares in 4 ways, for example, as 1512206359524 + 19929938775616 = 1229718^2 + 4464296^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21442145135140.

It is not an unprimeable number, because it can be changed into a prime (21442145135149) 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, 25460721 + ... + 26289400.

It is an arithmetic number, because the mean of its divisors is an integer number (1876278298293).

Almost surely, 2^{21442145135140} is an apocalyptic number.

21442145135140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21442145135140 is an abundant number, since it is smaller than the sum of its proper divisors (23588534023892).

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

21442145135140 is a wasteful number, since it uses less digits than its factorization.

21442145135140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51770847 (or 51770845 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 37.

Adding to 21442145135140 its reverse (4153154124412), we get a palindrome (25595299259552).

The spelling of 21442145135140 in words is "twenty-one trillion, four hundred forty-two billion, one hundred forty-five million, one hundred thirty-five thousand, one hundred forty".