1256211201366 has 24 divisors (see below), whose sum is σ = 2969226476424. Its totient is φ = 380670060960.

The previous prime is 1256211201331. The next prime is 1256211201397. The reversal of 1256211201366 is 6631021126521.

1256211201366 is a `hidden beast` number, since 1 + 2 + 5 + 621 + 1 + 20 + 1 + 3 + 6 + 6 = 666.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1256211201366.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3172250311 + ... + 3172250706.

It is an arithmetic number, because the mean of its divisors is an integer number (123717769851).

Almost surely, 2^{1256211201366} is an apocalyptic number.

1256211201366 is an abundant number, since it is smaller than the sum of its proper divisors (1713015275058).

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

1256211201366 is a wasteful number, since it uses less digits than its factorization.

1256211201366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6344501036 (or 6344501033 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

Adding to 1256211201366 its reverse (6631021126521), we get a palindrome (7887232327887).

The spelling of 1256211201366 in words is "one trillion, two hundred fifty-six billion, two hundred eleven million, two hundred one thousand, three hundred sixty-six".