20515551421422 has 16 divisors (see below), whose sum is σ = 41037604440192. Its totient is φ = 6837433540920.

The previous prime is 20515551421369. The next prime is 20515551421433. The reversal of 20515551421422 is 22412415551502.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 270858868 + ... + 270934599.

It is an arithmetic number, because the mean of its divisors is an integer number (2564850277512).

Almost surely, 2^{20515551421422} is an apocalyptic number.

20515551421422 is an abundant number, since it is smaller than the sum of its proper divisors (20522053018770).

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

20515551421422 is a wasteful number, since it uses less digits than its factorization.

20515551421422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 541799783.

The product of its (nonzero) digits is 160000, while the sum is 39.

Adding to 20515551421422 its reverse (22412415551502), we get a palindrome (42927966972924).

The spelling of 20515551421422 in words is "twenty trillion, five hundred fifteen billion, five hundred fifty-one million, four hundred twenty-one thousand, four hundred twenty-two".