6420511 has 2 divisors, whose sum is σ = 6420512. Its totient is φ = 6420510.

The previous prime is 6420487. The next prime is 6420523. The reversal of 6420511 is 1150246.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6420511 - 2⁷ = 6420383 is a prime.

It is a super-3 number, since 3×6420511³ (a number of 21 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

6420511 is a lucky number.

It is a zygodrome in base 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6421511) 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, 3210255 + 3210256.

It is an arithmetic number, because the mean of its divisors is an integer number (3210256).

Almost surely, 2^6420511 is an apocalyptic number.

6420511 is a deficient number, since it is larger than the sum of its proper divisors (1).

6420511 is an equidigital number, since it uses as much as digits as its factorization.

6420511 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 6420511 is about 2533.8727276641. The cubic root of 6420511 is about 185.8616827299.

Adding to 6420511 its reverse (1150246), we get a palindrome (7570757).

The spelling of 6420511 in words is "six million, four hundred twenty thousand, five hundred eleven".