20201232421 has 4 divisors (see below), whose sum is σ = 21264455200. Its totient is φ = 19138009644.

The previous prime is 20201232407. The next prime is 20201232461. The reversal of 20201232421 is 12423210202.

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 20201232421 - 2⁹ = 20201231909 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 1063222759 = 20201232421 / (2 + 0 + 2 + 0 + 1 + 2 + 3 + 2 + 4 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20201232461) 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, 531611361 + ... + 531611398.

It is an arithmetic number, because the mean of its divisors is an integer number (5316113800).

Almost surely, 2^20201232421 is an apocalyptic number.

It is an amenable number.

20201232421 is a deficient number, since it is larger than the sum of its proper divisors (1063222779).

20201232421 is a wasteful number, since it uses less digits than its factorization.

20201232421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1063222778.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 20201232421 its reverse (12423210202), we get a palindrome (32624442623).

The spelling of 20201232421 in words is "twenty billion, two hundred one million, two hundred thirty-two thousand, four hundred twenty-one".