618549561551 has 2 divisors, whose sum is σ = 618549561552. Its totient is φ = 618549561550.

The previous prime is 618549561527. The next prime is 618549561563. The reversal of 618549561551 is 155165945816.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 618549561551 - 2³⁸ = 343671654607 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (618549563551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 309274780775 + 309274780776.

It is an arithmetic number, because the mean of its divisors is an integer number (309274780776).

Almost surely, 2^618549561551 is an apocalyptic number.

618549561551 is a deficient number, since it is larger than the sum of its proper divisors (1).

618549561551 is an equidigital number, since it uses as much as digits as its factorization.

618549561551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480000, while the sum is 56.

The spelling of 618549561551 in words is "six hundred eighteen billion, five hundred forty-nine million, five hundred sixty-one thousand, five hundred fifty-one".