1216260543451 has 4 divisors (see below), whose sum is σ = 1216294493392. Its totient is φ = 1216226593512.

The previous prime is 1216260543427. The next prime is 1216260543457. The reversal of 1216260543451 is 1543450626121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1216260543451 - 2²⁹ = 1215723672539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1216260543457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16921176 + ... + 16992901.

It is an arithmetic number, because the mean of its divisors is an integer number (304073623348).

Almost surely, 2^{1216260543451} is an apocalyptic number.

1216260543451 is a deficient number, since it is larger than the sum of its proper divisors (33949941).

1216260543451 is an equidigital number, since it uses as much as digits as its factorization.

1216260543451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33949940.

The product of its (nonzero) digits is 172800, while the sum is 40.

The spelling of 1216260543451 in words is "one trillion, two hundred sixteen billion, two hundred sixty million, five hundred forty-three thousand, four hundred fifty-one".