6642431 has 2 divisors, whose sum is σ = 6642432. Its totient is φ = 6642430.

The previous prime is 6642409. The next prime is 6642439. The reversal of 6642431 is 1342466.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6642431 is a prime.

It is a super-2 number, since 2×6642431² = 88243779179522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6642431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6642439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3321215 + 3321216.

It is an arithmetic number, because the mean of its divisors is an integer number (3321216).

Almost surely, 2^6642431 is an apocalyptic number.

6642431 is a deficient number, since it is larger than the sum of its proper divisors (1).

6642431 is an equidigital number, since it uses as much as digits as its factorization.

6642431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 26.

The square root of 6642431 is about 2577.2914076604. The cubic root of 6642431 is about 187.9788624945.

Adding to 6642431 its reverse (1342466), we get a palindrome (7984897).

The spelling of 6642431 in words is "six million, six hundred forty-two thousand, four hundred thirty-one".