1868618641 has 2 divisors, whose sum is σ = 1868618642. Its totient is φ = 1868618640.

The previous prime is 1868618639. The next prime is 1868618657. The reversal of 1868618641 is 1468168681.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1809651600 + 58967041 = 42540^2 + 7679^2 .

It is a cyclic number.

It is not a de Polignac number, because 1868618641 - 2¹ = 1868618639 is a prime.

Together with 1868618639, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1868615641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 934309320 + 934309321.

It is an arithmetic number, because the mean of its divisors is an integer number (934309321).

Almost surely, 2^1868618641 is an apocalyptic number.

It is an amenable number.

1868618641 is a deficient number, since it is larger than the sum of its proper divisors (1).

1868618641 is an equidigital number, since it uses as much as digits as its factorization.

1868618641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 442368, while the sum is 49.

The square root of 1868618641 is about 43227.5218003531. The cubic root of 1868618641 is about 1231.7055329521.

The spelling of 1868618641 in words is "one billion, eight hundred sixty-eight million, six hundred eighteen thousand, six hundred forty-one".