1218025779 has 8 divisors (see below), whose sum is σ = 1639802112. Its totient is φ = 804133320.

The previous prime is 1218025771. The next prime is 1218025793. The reversal of 1218025779 is 9775208121.

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

It is not a de Polignac number, because 1218025779 - 2³ = 1218025771 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1218025779.

It is not an unprimeable number, because it can be changed into a prime (1218025771) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1970607 + ... + 1971224.

It is an arithmetic number, because the mean of its divisors is an integer number (204975264).

Almost surely, 2^1218025779 is an apocalyptic number.

1218025779 is a deficient number, since it is larger than the sum of its proper divisors (421776333).

1218025779 is a wasteful number, since it uses less digits than its factorization.

1218025779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3941937.

The product of its (nonzero) digits is 70560, while the sum is 42.

The square root of 1218025779 is about 34900.2260594398. The cubic root of 1218025779 is about 1067.9530490729.

The spelling of 1218025779 in words is "one billion, two hundred eighteen million, twenty-five thousand, seven hundred seventy-nine".