6420431 has 2 divisors, whose sum is σ = 6420432. Its totient is φ = 6420430.

The previous prime is 6420413. The next prime is 6420437. The reversal of 6420431 is 1340246.

It is a happy number.

Together with previous prime (6420413) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6420431 - 2¹⁰ = 6419407 is a prime.

It is a super-2 number, since 2×6420431² = 82443868451522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6420437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3210215 + 3210216.

It is an arithmetic number, because the mean of its divisors is an integer number (3210216).

Almost surely, 2^6420431 is an apocalyptic number.

6420431 is a deficient number, since it is larger than the sum of its proper divisors (1).

6420431 is an equidigital number, since it uses as much as digits as its factorization.

6420431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 6420431 is about 2533.8569415024. The cubic root of 6420431 is about 185.8609107770.

Adding to 6420431 its reverse (1340246), we get a palindrome (7760677).

The spelling of 6420431 in words is "six million, four hundred twenty thousand, four hundred thirty-one".