1212865617 has 4 divisors (see below), whose sum is σ = 1617154160. Its totient is φ = 808577076.

The previous prime is 1212865609. The next prime is 1212865631. The reversal of 1212865617 is 7165682121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1212865617 - 2³ = 1212865609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1212865657) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 202144267 + ... + 202144272.

It is an arithmetic number, because the mean of its divisors is an integer number (404288540).

Almost surely, 2^1212865617 is an apocalyptic number.

It is an amenable number.

1212865617 is a deficient number, since it is larger than the sum of its proper divisors (404288543).

1212865617 is an equidigital number, since it uses as much as digits as its factorization.

1212865617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404288542.

The product of its digits is 40320, while the sum is 39.

The square root of 1212865617 is about 34826.2202514140. The cubic root of 1212865617 is about 1066.4427878558.

The spelling of 1212865617 in words is "one billion, two hundred twelve million, eight hundred sixty-five thousand, six hundred seventeen".