1216564202751 has 16 divisors (see below), whose sum is σ = 1647490279680. Its totient is φ = 798375997440.

The previous prime is 1216564202747. The next prime is 1216564202761. The reversal of 1216564202751 is 1572024656121.

It is not a de Polignac number, because 1216564202751 - 2² = 1216564202747 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216564202741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4304386 + ... + 4578303.

It is an arithmetic number, because the mean of its divisors is an integer number (102968142480).

Almost surely, 2^{1216564202751} is an apocalyptic number.

1216564202751 is a deficient number, since it is larger than the sum of its proper divisors (430926076929).

1216564202751 is an equidigital number, since it uses as much as digits as its factorization.

1216564202751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8883406.

The product of its (nonzero) digits is 201600, while the sum is 42.

Adding to 1216564202751 its reverse (1572024656121), we get a palindrome (2788588858872).

The spelling of 1216564202751 in words is "one trillion, two hundred sixteen billion, five hundred sixty-four million, two hundred two thousand, seven hundred fifty-one".