231420421 has 2 divisors, whose sum is σ = 231420422. Its totient is φ = 231420420.

The previous prime is 231420401. The next prime is 231420451. The reversal of 231420421 is 124024132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 198415396 + 33005025 = 14086^2 + 5745^2 .

It is a cyclic number.

It is not a de Polignac number, because 231420421 - 2¹¹ = 231418373 is a prime.

It is a super-2 number, since 2×231420421² = 107110822511634482, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231420401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115710210 + 115710211.

It is an arithmetic number, because the mean of its divisors is an integer number (115710211).

Almost surely, 2^231420421 is an apocalyptic number.

It is an amenable number.

231420421 is a deficient number, since it is larger than the sum of its proper divisors (1).

231420421 is an equidigital number, since it uses as much as digits as its factorization.

231420421 is an odious number, because the sum of its binary digits is odd.

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

The square root of 231420421 is about 15212.5087017231. The cubic root of 231420421 is about 613.9512573288.

Adding to 231420421 its reverse (124024132), we get a palindrome (355444553).

The spelling of 231420421 in words is "two hundred thirty-one million, four hundred twenty thousand, four hundred twenty-one".