1217986668 has 18 divisors (see below), whose sum is σ = 3078799724. Its totient is φ = 405995544.

The previous prime is 1217986667. The next prime is 1217986669. The reversal of 1217986668 is 8666897121.

It is an interprime number because it is at equal distance from previous prime (1217986667) and next prime (1217986669).

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (1217986661) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 16916446 + ... + 16916517.

Almost surely, 2^1217986668 is an apocalyptic number.

1217986668 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1217986668 is an abundant number, since it is smaller than the sum of its proper divisors (1860813056).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1217986668 is a wasteful number, since it uses less digits than its factorization.

1217986668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33832973 (or 33832968 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 54.

The square root of 1217986668 is about 34899.6657290582. The cubic root of 1217986668 is about 1067.9416182369.

The spelling of 1217986668 in words is "one billion, two hundred seventeen million, nine hundred eighty-six thousand, six hundred sixty-eight".