20404201421 has 4 divisors (see below), whose sum is σ = 20413465632. Its totient is φ = 20394937212.

The previous prime is 20404201417. The next prime is 20404201423. The reversal of 20404201421 is 12410240402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20404201421 - 2² = 20404201417 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20404201393 and 20404201402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20404201423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4628801 + ... + 4633206.

It is an arithmetic number, because the mean of its divisors is an integer number (5103366408).

Almost surely, 2^20404201421 is an apocalyptic number.

It is an amenable number.

20404201421 is a deficient number, since it is larger than the sum of its proper divisors (9264211).

20404201421 is an equidigital number, since it uses as much as digits as its factorization.

20404201421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9264210.

The product of its (nonzero) digits is 512, while the sum is 20.

Adding to 20404201421 its reverse (12410240402), we get a palindrome (32814441823).

The spelling of 20404201421 in words is "twenty billion, four hundred four million, two hundred one thousand, four hundred twenty-one".