21142420424 has 32 divisors (see below), whose sum is σ = 39823358400. Its totient is φ = 10522966080.

The previous prime is 21142420421. The next prime is 21142420441. The reversal of 21142420424 is 42402424112.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21142420393 and 21142420402.

It is not an unprimeable number, because it can be changed into a prime (21142420421) 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, 1679594 + ... + 1692134.

It is an arithmetic number, because the mean of its divisors is an integer number (1244479950).

Almost surely, 2^21142420424 is an apocalyptic number.

It is an amenable number.

21142420424 is a deficient number, since it is larger than the sum of its proper divisors (18680937976).

21142420424 is a wasteful number, since it uses less digits than its factorization.

21142420424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13493 (or 13489 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 26.

Adding to 21142420424 its reverse (42402424112), we get a palindrome (63544844536).

The spelling of 21142420424 in words is "twenty-one billion, one hundred forty-two million, four hundred twenty thousand, four hundred twenty-four".