1145216681 has 6 divisors (see below), whose sum is σ = 1332190890. Its totient is φ = 981614256.

The previous prime is 1145216651. The next prime is 1145216689. The reversal of 1145216681 is 1866125411.

It can be written as a sum of positive squares in only one way, i.e., 715027600 + 430189081 = 26740^2 + 20741^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1145216681 is a prime.

It is a super-2 number, since 2×1145216681² = 2623042492881311522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1145216689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11685836 + ... + 11685933.

It is an arithmetic number, because the mean of its divisors is an integer number (222031815).

Almost surely, 2^1145216681 is an apocalyptic number.

It is an amenable number.

1145216681 is a deficient number, since it is larger than the sum of its proper divisors (186974209).

1145216681 is an equidigital number, since it uses as much as digits as its factorization.

1145216681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23371783 (or 23371776 counting only the distinct ones).

The product of its digits is 11520, while the sum is 35.

The square root of 1145216681 is about 33841.0502348849. The cubic root of 1145216681 is about 1046.2349451587.

The spelling of 1145216681 in words is "one billion, one hundred forty-five million, two hundred sixteen thousand, six hundred eighty-one".