21142142412 has 96 divisors (see below), whose sum is σ = 52953626880. Its totient is φ = 6541946880.

The previous prime is 21142142389. The next prime is 21142142449. The reversal of 21142142412 is 21424124112.

It is a happy number.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5258539 + ... + 5262557.

It is an arithmetic number, because the mean of its divisors is an integer number (551600280).

Almost surely, 2^21142142412 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21142142412, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26476813440).

21142142412 is an abundant number, since it is smaller than the sum of its proper divisors (31811484468).

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

21142142412 is a wasteful number, since it uses less digits than its factorization.

21142142412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4391 (or 4389 counting only the distinct ones).

The product of its digits is 1024, while the sum is 24.

Adding to 21142142412 its reverse (21424124112), we get a palindrome (42566266524).

The spelling of 21142142412 in words is "twenty-one billion, one hundred forty-two million, one hundred forty-two thousand, four hundred twelve".