618646513 has 4 divisors (see below), whose sum is σ = 624771828. Its totient is φ = 612521200.

The previous prime is 618646493. The next prime is 618646619. The reversal of 618646513 is 315646816.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 395532544 + 223113969 = 19888^2 + 14937^2 .

It is a cyclic number.

It is not a de Polignac number, because 618646513 - 2⁹ = 618646001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (618646313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3062506 + ... + 3062707.

It is an arithmetic number, because the mean of its divisors is an integer number (156192957).

Almost surely, 2^618646513 is an apocalyptic number.

It is an amenable number.

618646513 is a deficient number, since it is larger than the sum of its proper divisors (6125315).

618646513 is a wasteful number, since it uses less digits than its factorization.

618646513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6125314.

The product of its digits is 103680, while the sum is 40.

The square root of 618646513 is about 24872.6056737126. The cubic root of 618646513 is about 852.0809511312.

The spelling of 618646513 in words is "six hundred eighteen million, six hundred forty-six thousand, five hundred thirteen".