21213405434342 has 16 divisors (see below), whose sum is σ = 34713123664464. Its totient is φ = 9642379680000.

The previous prime is 21213405434341. The next prime is 21213405434357. The reversal of 21213405434342 is 24343450431212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21213405434296 and 21213405434305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213405434341) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1014659 + ... + 6592142.

It is an arithmetic number, because the mean of its divisors is an integer number (2169570229029).

Almost surely, 2^{21213405434342} is an apocalyptic number.

21213405434342 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21213405434342 is a deficient number, since it is larger than the sum of its proper divisors (13499718230122).

21213405434342 is a wasteful number, since it uses less digits than its factorization.

21213405434342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7733575.

The product of its (nonzero) digits is 276480, while the sum is 38.

Adding to 21213405434342 its reverse (24343450431212), we get a palindrome (45556855865554).

The spelling of 21213405434342 in words is "twenty-one trillion, two hundred thirteen billion, four hundred five million, four hundred thirty-four thousand, three hundred forty-two".