6421931 has 2 divisors, whose sum is σ = 6421932. Its totient is φ = 6421930.

The previous prime is 6421913. The next prime is 6421967. The reversal of 6421931 is 1391246.

Together with previous prime (6421913) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6421931 - 2¹⁰ = 6420907 is a prime.

It is a super-2 number, since 2×6421931² = 82482395537522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 6421931.

It is not a weakly prime, because it can be changed into another prime (6421901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3210965 + 3210966.

It is an arithmetic number, because the mean of its divisors is an integer number (3210966).

Almost surely, 2^6421931 is an apocalyptic number.

6421931 is a deficient number, since it is larger than the sum of its proper divisors (1).

6421931 is an equidigital number, since it uses as much as digits as its factorization.

6421931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 26.

The square root of 6421931 is about 2534.1529156702. The cubic root of 6421931 is about 185.8753838271.

The spelling of 6421931 in words is "six million, four hundred twenty-one thousand, nine hundred thirty-one".