21455442420342 has 64 divisors (see below), whose sum is σ = 49067655897600. Its totient is φ = 6126796638720.

The previous prime is 21455442420337. The next prime is 21455442420353. The reversal of 21455442420342 is 24302424455412.

It is a super-2 number, since 2×21455442420342² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 21455442420294 and 21455442420303.

It is a congruent number.

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, 945537217 + ... + 945559907.

It is an arithmetic number, because the mean of its divisors is an integer number (766682123400).

Almost surely, 2^{21455442420342} is an apocalyptic number.

21455442420342 is an abundant number, since it is smaller than the sum of its proper divisors (27612213477258).

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

21455442420342 is a wasteful number, since it uses less digits than its factorization.

21455442420342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33941.

The product of its (nonzero) digits is 1228800, while the sum is 42.

Adding to 21455442420342 its reverse (24302424455412), we get a palindrome (45757866875754).

The spelling of 21455442420342 in words is "twenty-one trillion, four hundred fifty-five billion, four hundred forty-two million, four hundred twenty thousand, three hundred forty-two".