21152421342 has 48 divisors (see below), whose sum is σ = 49834887648. Its totient is φ = 6445241280.

The previous prime is 21152421341. The next prime is 21152421349. The reversal of 21152421342 is 24312425112.

21152421342 is a `hidden beast` number, since 2 + 1 + 1 + 524 + 2 + 134 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21152421341) 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 23 ways as a sum of consecutive naturals, for example, 414709 + ... + 462912.

It is an arithmetic number, because the mean of its divisors is an integer number (1038226826).

Almost surely, 2^21152421342 is an apocalyptic number.

21152421342 is an abundant number, since it is smaller than the sum of its proper divisors (28682466306).

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

21152421342 is a wasteful number, since it uses less digits than its factorization.

21152421342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 877745 (or 877742 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

Adding to 21152421342 its reverse (24312425112), we get a palindrome (45464846454).

The spelling of 21152421342 in words is "twenty-one billion, one hundred fifty-two million, four hundred twenty-one thousand, three hundred forty-two".