21131144342 has 16 divisors (see below), whose sum is σ = 39517984512. Its totient is φ = 8232913320.

The previous prime is 21131144341. The next prime is 21131144369. The reversal of 21131144342 is 24344113112.

It is a super-2 number, since 2×21131144342² (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 (21131144341) 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, 68607458 + ... + 68607765.

It is an arithmetic number, because the mean of its divisors is an integer number (2469874032).

Almost surely, 2^21131144342 is an apocalyptic number.

21131144342 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21131144342 is a deficient number, since it is larger than the sum of its proper divisors (18386840170).

21131144342 is a wasteful number, since it uses less digits than its factorization.

21131144342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137215243.

The product of its digits is 2304, while the sum is 26.

Adding to 21131144342 its reverse (24344113112), we get a palindrome (45475257454).

The spelling of 21131144342 in words is "twenty-one billion, one hundred thirty-one million, one hundred forty-four thousand, three hundred forty-two".