1218222639256 has 32 divisors (see below), whose sum is σ = 2615048916480. Its totient is φ = 521181050400.

The previous prime is 1218222639253. The next prime is 1218222639269. The reversal of 1218222639256 is 6529362228121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218222639251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19017040 + ... + 19080991.

It is an arithmetic number, because the mean of its divisors is an integer number (81720278640).

Almost surely, 2^{1218222639256} is an apocalyptic number.

It is an amenable number.

1218222639256 is an abundant number, since it is smaller than the sum of its proper divisors (1396826277224).

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

1218222639256 is a wasteful number, since it uses less digits than its factorization.

1218222639256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38098615 (or 38098611 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 49.

The spelling of 1218222639256 in words is "one trillion, two hundred eighteen billion, two hundred twenty-two million, six hundred thirty-nine thousand, two hundred fifty-six".