1663043026361 has 4 divisors (see below), whose sum is σ = 1664817886452. Its totient is φ = 1661268166272.

The previous prime is 1663043026349. The next prime is 1663043026363. The reversal of 1663043026361 is 1636203403661.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 371558517136 + 1291484509225 = 609556^2 + 1136435^2 .

It is a cyclic number.

It is not a de Polignac number, because 1663043026361 - 2¹⁰ = 1663043025337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1663043026363) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 887428640 + ... + 887430513.

It is an arithmetic number, because the mean of its divisors is an integer number (416204471613).

Almost surely, 2^{1663043026361} is an apocalyptic number.

It is an amenable number.

1663043026361 is a deficient number, since it is larger than the sum of its proper divisors (1774860091).

1663043026361 is an equidigital number, since it uses as much as digits as its factorization.

1663043026361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1774860090.

The product of its (nonzero) digits is 279936, while the sum is 41.

The spelling of 1663043026361 in words is "one trillion, six hundred sixty-three billion, forty-three million, twenty-six thousand, three hundred sixty-one".