6421111 has 2 divisors, whose sum is σ = 6421112. Its totient is φ = 6421110.

The previous prime is 6421099. The next prime is 6421127. The reversal of 6421111 is 1111246.

It is an a-pointer prime, because the next prime (6421127) can be obtained adding 6421111 to its sum of digits (16).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6421111 - 2⁹ = 6420599 is a prime.

6421111 is a modest number, since divided by 1111 gives 642 as remainder.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6421141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3210555 + 3210556.

It is an arithmetic number, because the mean of its divisors is an integer number (3210556).

Almost surely, 2^6421111 is an apocalyptic number.

6421111 is a deficient number, since it is larger than the sum of its proper divisors (1).

6421111 is an equidigital number, since it uses as much as digits as its factorization.

6421111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48, while the sum is 16.

The square root of 6421111 is about 2533.9911207421. The cubic root of 6421111 is about 185.8674721724.

Adding to 6421111 its reverse (1111246), we get a palindrome (7532357).

The spelling of 6421111 in words is "six million, four hundred twenty-one thousand, one hundred eleven".