21142120412 has 24 divisors (see below), whose sum is σ = 42915352704. Its totient is φ = 8925670512.

The previous prime is 21142120411. The next prime is 21142120429. The reversal of 21142120412 is 21402124112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21142120411) 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 7 ways as a sum of consecutive naturals, for example, 5633018 + ... + 5636769.

It is an arithmetic number, because the mean of its divisors is an integer number (1788139696).

Almost surely, 2^21142120412 is an apocalyptic number.

It is an amenable number.

21142120412 is an abundant number, since it is smaller than the sum of its proper divisors (21773232292).

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

21142120412 is a wasteful number, since it uses less digits than its factorization.

21142120412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11269865 (or 11269863 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21142120412 its reverse (21402124112), we get a palindrome (42544244524).

The spelling of 21142120412 in words is "twenty-one billion, one hundred forty-two million, one hundred twenty thousand, four hundred twelve".