1218965601 has 24 divisors (see below), whose sum is σ = 1951636224. Its totient is φ = 674079840.

The previous prime is 1218965581. The next prime is 1218965669. The reversal of 1218965601 is 1065698121.

It is not a de Polignac number, because 1218965601 - 2⁶ = 1218965537 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1218965601.

It is not an unprimeable number, because it can be changed into a prime (1218965681) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 129190 + ... + 138303.

It is an arithmetic number, because the mean of its divisors is an integer number (81318176).

Almost surely, 2^1218965601 is an apocalyptic number.

It is an amenable number.

1218965601 is a deficient number, since it is larger than the sum of its proper divisors (732670623).

1218965601 is a wasteful number, since it uses less digits than its factorization.

1218965601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267541 (or 267534 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 39.

The square root of 1218965601 is about 34913.6878745285. The cubic root of 1218965601 is about 1068.2276540258.

The spelling of 1218965601 in words is "one billion, two hundred eighteen million, nine hundred sixty-five thousand, six hundred one".