21221522145142 has 16 divisors (see below), whose sum is σ = 34747736493312. Its totient is φ = 9640143833320.

The previous prime is 21221522145113. The next prime is 21221522145149. The reversal of 21221522145142 is 24154122512212.

It is a junction number, because it is equal to n+sod(n) for n = 21221522145098 and 21221522145107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221522145149) 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, 300093658 + ... + 300164365.

It is an arithmetic number, because the mean of its divisors is an integer number (2171733530832).

Almost surely, 2^{21221522145142} is an apocalyptic number.

21221522145142 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21221522145142 is a deficient number, since it is larger than the sum of its proper divisors (13526214348170).

21221522145142 is a wasteful number, since it uses less digits than its factorization.

21221522145142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 600259643.

The product of its digits is 25600, while the sum is 34.

Adding to 21221522145142 its reverse (24154122512212), we get a palindrome (45375644657354).

The spelling of 21221522145142 in words is "twenty-one trillion, two hundred twenty-one billion, five hundred twenty-two million, one hundred forty-five thousand, one hundred forty-two".