20780105421 has 16 divisors (see below), whose sum is σ = 29432638400. Its totient is φ = 13003867008.

The previous prime is 20780105413. The next prime is 20780105447. The reversal of 20780105421 is 12450108702.

It is not a de Polignac number, because 20780105421 - 2³ = 20780105413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20780105821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1666096 + ... + 1678521.

It is an arithmetic number, because the mean of its divisors is an integer number (1839539900).

Almost surely, 2^20780105421 is an apocalyptic number.

It is an amenable number.

20780105421 is a deficient number, since it is larger than the sum of its proper divisors (8652532979).

20780105421 is a wasteful number, since it uses less digits than its factorization.

20780105421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3344748.

The product of its (nonzero) digits is 4480, while the sum is 30.

The spelling of 20780105421 in words is "twenty billion, seven hundred eighty million, one hundred five thousand, four hundred twenty-one".