20402242420 has 24 divisors (see below), whose sum is σ = 48965382144. Its totient is φ = 6995054496.

The previous prime is 20402242403. The next prime is 20402242423. The reversal of 20402242420 is 2424220402.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 20402242391 and 20402242400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20402242423) 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, 72865012 + ... + 72865291.

It is an arithmetic number, because the mean of its divisors is an integer number (2040224256).

Almost surely, 2^20402242420 is an apocalyptic number.

20402242420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20402242420 is an abundant number, since it is smaller than the sum of its proper divisors (28563139724).

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

20402242420 is a wasteful number, since it uses less digits than its factorization.

20402242420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145730319 (or 145730317 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 22.

Adding to 20402242420 its reverse (2424220402), we get a palindrome (22826462822).

The spelling of 20402242420 in words is "twenty billion, four hundred two million, two hundred forty-two thousand, four hundred twenty".