21420242433 has 12 divisors (see below), whose sum is σ = 31598656128. Its totient is φ = 13976328120.

The previous prime is 21420242407. The next prime is 21420242449. The reversal of 21420242433 is 33424202412.

21420242433 is a `hidden beast` number, since 2 + 1 + 4 + 202 + 424 + 33 = 666.

It is not a de Polignac number, because 21420242433 - 2²⁰ = 21419193857 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21420242397 and 21420242406.

It is not an unprimeable number, because it can be changed into a prime (21420242633) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25319013 + ... + 25319858.

It is an arithmetic number, because the mean of its divisors is an integer number (2633221344).

Almost surely, 2^21420242433 is an apocalyptic number.

It is an amenable number.

21420242433 is a deficient number, since it is larger than the sum of its proper divisors (10178413695).

21420242433 is a wasteful number, since it uses less digits than its factorization.

21420242433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50638924 (or 50638921 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 27.

Adding to 21420242433 its reverse (33424202412), we get a palindrome (54844444845).

The spelling of 21420242433 in words is "twenty-one billion, four hundred twenty million, two hundred forty-two thousand, four hundred thirty-three".