21142020042 has 96 divisors (see below), whose sum is σ = 53952889536. Its totient is φ = 5898816000.

The previous prime is 21142020013. The next prime is 21142020059. The reversal of 21142020042 is 24002024112.

21142020042 is a `hidden beast` number, since 2 + 1 + 1 + 420 + 200 + 42 = 666.

It is a super-2 number, since 2×21142020042² (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).

It is a junction number, because it is equal to n+sod(n) for n = 21142019997 and 21142020024.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 1021933 + ... + 1042415.

It is an arithmetic number, because the mean of its divisors is an integer number (562009266).

Almost surely, 2^21142020042 is an apocalyptic number.

21142020042 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 21142020042, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26976444768).

21142020042 is an abundant number, since it is smaller than the sum of its proper divisors (32810869494).

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

21142020042 is a wasteful number, since it uses less digits than its factorization.

21142020042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20916 (or 20913 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21142020042 its reverse (24002024112), we get a palindrome (45144044154).

The spelling of 21142020042 in words is "twenty-one billion, one hundred forty-two million, twenty thousand, forty-two".