1556248765009 has 27 divisors (see below), whose sum is σ = 1651667540187. Its totient is φ = 1466218154016.

The previous prime is 1556248764977. The next prime is 1556248765013. The reversal of 1556248765009 is 9005678426551.

It is a happy number.

The square root of 1556248765009 is 1247497.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 883402611025 + 672846153984 = 939895^2 + 820272^2 .

It is not a de Polignac number, because 1556248765009 - 2⁵ = 1556248764977 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1556248763009) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2094547092 + ... + 2094547834.

Almost surely, 2^{1556248765009} is an apocalyptic number.

1556248765009 is the 1247497-th square number.

1556248765009 is the 623749-th centered octagonal number.

It is an amenable number.

1556248765009 is a deficient number, since it is larger than the sum of its proper divisors (95418775178).

1556248765009 is an frugal number, since it uses more digits than its factorization.

1556248765009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1678 (or 839 counting only the distinct ones).

The product of its (nonzero) digits is 18144000, while the sum is 58.

The spelling of 1556248765009 in words is "one trillion, five hundred fifty-six billion, two hundred forty-eight million, seven hundred sixty-five thousand, nine".