618880786621 has 2 divisors, whose sum is σ = 618880786622. Its totient is φ = 618880786620.

The previous prime is 618880786607. The next prime is 618880786627. The reversal of 618880786621 is 126687088816.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 575944388100 + 42936398521 = 758910^2 + 207211^2 .

It is a cyclic number.

It is not a de Polignac number, because 618880786621 - 2¹³ = 618880778429 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 618880786621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (618880786627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 309440393310 + 309440393311.

It is an arithmetic number, because the mean of its divisors is an integer number (309440393311).

Almost surely, 2^618880786621 is an apocalyptic number.

It is an amenable number.

618880786621 is a deficient number, since it is larger than the sum of its proper divisors (1).

618880786621 is an equidigital number, since it uses as much as digits as its factorization.

618880786621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12386304, while the sum is 61.

The spelling of 618880786621 in words is "six hundred eighteen billion, eight hundred eighty million, seven hundred eighty-six thousand, six hundred twenty-one".