20010231421 has 2 divisors, whose sum is σ = 20010231422. Its totient is φ = 20010231420.

The previous prime is 20010231419. The next prime is 20010231427. The reversal of 20010231421 is 12413201002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17952248196 + 2057983225 = 133986^2 + 45365^2 .

It is a cyclic number.

It is not a de Polignac number, because 20010231421 - 2¹ = 20010231419 is a prime.

Together with 20010231419, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 20010231395 and 20010231404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20010231427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10005115710 + 10005115711.

It is an arithmetic number, because the mean of its divisors is an integer number (10005115711).

Almost surely, 2^20010231421 is an apocalyptic number.

It is an amenable number.

20010231421 is a deficient number, since it is larger than the sum of its proper divisors (1).

20010231421 is an equidigital number, since it uses as much as digits as its factorization.

20010231421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 20010231421 its reverse (12413201002), we get a palindrome (32423432423).

The spelling of 20010231421 in words is "twenty billion, ten million, two hundred thirty-one thousand, four hundred twenty-one".