6618551 has 2 divisors, whose sum is σ = 6618552. Its totient is φ = 6618550.

The previous prime is 6618533. The next prime is 6618553. The reversal of 6618551 is 1558166.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6618551 - 2⁶ = 6618487 is a prime.

Together with 6618553, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6618553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3309275 + 3309276.

It is an arithmetic number, because the mean of its divisors is an integer number (3309276).

Almost surely, 2^6618551 is an apocalyptic number.

6618551 is a deficient number, since it is larger than the sum of its proper divisors (1).

6618551 is an equidigital number, since it uses as much as digits as its factorization.

6618551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 32.

The square root of 6618551 is about 2572.6544657221. The cubic root of 6618551 is about 187.7533263241.

The spelling of 6618551 in words is "six million, six hundred eighteen thousand, five hundred fifty-one".