12018551 has 2 divisors, whose sum is σ = 12018552. Its totient is φ = 12018550.

The previous prime is 12018547. The next prime is 12018553. The reversal of 12018551 is 15581021.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 12018551 - 2² = 12018547 is a prime.

It is a Sophie Germain prime.

Together with 12018553, 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 (12018553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6009275 + 6009276.

It is an arithmetic number, because the mean of its divisors is an integer number (6009276).

Almost surely, 2^12018551 is an apocalyptic number.

12018551 is a deficient number, since it is larger than the sum of its proper divisors (1).

12018551 is an equidigital number, since it uses as much as digits as its factorization.

12018551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 400, while the sum is 23.

The square root of 12018551 is about 3466.7781873088. The cubic root of 12018551 is about 229.0607632911.

Adding to 12018551 its reverse (15581021), we get a palindrome (27599572).

The spelling of 12018551 in words is "twelve million, eighteen thousand, five hundred fifty-one".