21142343442 has 64 divisors (see below), whose sum is σ = 48597143040. Its totient is φ = 6064502400.

The previous prime is 21142343441. The next prime is 21142343447. The reversal of 21142343442 is 24434324112.

It is not an unprimeable number, because it can be changed into a prime (21142343441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1650153 + ... + 1662915.

It is an arithmetic number, because the mean of its divisors is an integer number (759330360).

Almost surely, 2^21142343442 is an apocalyptic number.

21142343442 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21142343442, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24298571520).

21142343442 is an abundant number, since it is smaller than the sum of its proper divisors (27454799598).

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

21142343442 is a wasteful number, since it uses less digits than its factorization.

21142343442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14119.

The product of its digits is 18432, while the sum is 30.

Adding to 21142343442 its reverse (24434324112), we get a palindrome (45576667554).

The spelling of 21142343442 in words is "twenty-one billion, one hundred forty-two million, three hundred forty-three thousand, four hundred forty-two".