1216770865 has 8 divisors (see below), whose sum is σ = 1484873280. Its totient is φ = 956917872.

The previous prime is 1216770859. The next prime is 1216770883. The reversal of 1216770865 is 5680776121.

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

It is a cyclic number.

It is not a de Polignac number, because 1216770865 - 2³ = 1216770857 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2062029 + ... + 2062618.

It is an arithmetic number, because the mean of its divisors is an integer number (185609160).

Almost surely, 2^1216770865 is an apocalyptic number.

It is an amenable number.

1216770865 is a deficient number, since it is larger than the sum of its proper divisors (268102415).

1216770865 is an equidigital number, since it uses as much as digits as its factorization.

1216770865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4124711.

The product of its (nonzero) digits is 141120, while the sum is 43.

The square root of 1216770865 is about 34882.2428321345. The cubic root of 1216770865 is about 1067.5861576167.

The spelling of 1216770865 in words is "one billion, two hundred sixteen million, seven hundred seventy thousand, eight hundred sixty-five".