121618559 has 2 divisors, whose sum is σ = 121618560. Its totient is φ = 121618558.

The previous prime is 121618543. The next prime is 121618597. The reversal of 121618559 is 955816121.

It is an a-pointer prime, because the next prime (121618597) can be obtained adding 121618559 to its sum of digits (38).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121618559 - 2⁴ = 121618543 is a prime.

It is a Sophie Germain prime.

It is a zygodrome in base 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121678559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60809279 + 60809280.

It is an arithmetic number, because the mean of its divisors is an integer number (60809280).

Almost surely, 2^121618559 is an apocalyptic number.

121618559 is a deficient number, since it is larger than the sum of its proper divisors (1).

121618559 is an equidigital number, since it uses as much as digits as its factorization.

121618559 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21600, while the sum is 38.

The square root of 121618559 is about 11028.0804766741. The cubic root of 121618559 is about 495.4501350417.

The spelling of 121618559 in words is "one hundred twenty-one million, six hundred eighteen thousand, five hundred fifty-nine".