1217988266 has 8 divisors (see below), whose sum is σ = 1993071744. Its totient is φ = 553631020.

The previous prime is 1217988257. The next prime is 1217988269. The reversal of 1217988266 is 6628897121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×1217988266² = 2966990832227373512, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1217988269) 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, 27681530 + ... + 27681573.

It is an arithmetic number, because the mean of its divisors is an integer number (249133968).

Almost surely, 2^1217988266 is an apocalyptic number.

1217988266 is a deficient number, since it is larger than the sum of its proper divisors (775083478).

1217988266 is a wasteful number, since it uses less digits than its factorization.

1217988266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55363116.

The product of its digits is 580608, while the sum is 50.

The square root of 1217988266 is about 34899.6886232528. The cubic root of 1217988266 is about 1067.9420852836.

The spelling of 1217988266 in words is "one billion, two hundred seventeen million, nine hundred eighty-eight thousand, two hundred sixty-six".