1218365201 has 4 divisors (see below), whose sum is σ = 1219205172. Its totient is φ = 1217525232.

The previous prime is 1218365153. The next prime is 1218365243. The reversal of 1218365201 is 1025638121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1025638121 = 107 ⋅9585403.

It can be written as a sum of positive squares in 2 ways, for example, as 516380176 + 701985025 = 22724^2 + 26495^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1218365201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1218365251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 417806 + ... + 420711.

It is an arithmetic number, because the mean of its divisors is an integer number (304801293).

Almost surely, 2^1218365201 is an apocalyptic number.

It is an amenable number.

1218365201 is a deficient number, since it is larger than the sum of its proper divisors (839971).

1218365201 is an equidigital number, since it uses as much as digits as its factorization.

1218365201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 839970.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 1218365201 is about 34905.0884685886. The cubic root of 1218365201 is about 1068.0522404859.

The spelling of 1218365201 in words is "one billion, two hundred eighteen million, three hundred sixty-five thousand, two hundred one".