1205215678 has 8 divisors (see below), whose sum is σ = 1811851200. Its totient is φ = 601265280.

The previous prime is 1205215673. The next prime is 1205215691. The reversal of 1205215678 is 8765125021.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1205215673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 670158 + ... + 671953.

It is an arithmetic number, because the mean of its divisors is an integer number (226481400).

Almost surely, 2^1205215678 is an apocalyptic number.

1205215678 is a deficient number, since it is larger than the sum of its proper divisors (606635522).

1205215678 is a wasteful number, since it uses less digits than its factorization.

1205215678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1342562.

The product of its (nonzero) digits is 33600, while the sum is 37.

The square root of 1205215678 is about 34716.2163548967. The cubic root of 1205215678 is about 1064.1959231563.

It can be divided in two parts, 12052 and 15678, that added together give a triangular number (27730 = T₂₃₅).

The spelling of 1205215678 in words is "one billion, two hundred five million, two hundred fifteen thousand, six hundred seventy-eight".