21212012142 has 12 divisors (see below), whose sum is σ = 45959359680. Its totient is φ = 7070670708.

The previous prime is 21212012141. The next prime is 21212012149. The reversal of 21212012142 is 24121021212.

It is a super-2 number, since 2×21212012142² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18), and also a Moran number because the ratio is a prime number: 1178445119 = 21212012142 / (2 + 1 + 2 + 1 + 2 + 0 + 1 + 2 + 1 + 4 + 2).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212012141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 589222542 + ... + 589222577.

It is an arithmetic number, because the mean of its divisors is an integer number (3829946640).

Almost surely, 2^21212012142 is an apocalyptic number.

21212012142 is an abundant number, since it is smaller than the sum of its proper divisors (24747347538).

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

21212012142 is a wasteful number, since it uses less digits than its factorization.

21212012142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1178445127 (or 1178445124 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21212012142 its reverse (24121021212), we get a palindrome (45333033354).

The spelling of 21212012142 in words is "twenty-one billion, two hundred twelve million, twelve thousand, one hundred forty-two".