1001263540523 has 4 divisors (see below), whose sum is σ = 1001288625240. Its totient is φ = 1001238455808.

The previous prime is 1001263540513. The next prime is 1001263540547. The reversal of 1001263540523 is 3250453621001.

It is a happy number.

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 1001263540523 - 2⁸ = 1001263540267 is a prime.

It is a super-2 number, since 2×1001263540523² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1001263540523.

It is not an unprimeable number, because it can be changed into a prime (1001263540513) 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, 12482390 + ... + 12562347.

It is an arithmetic number, because the mean of its divisors is an integer number (250322156310).

Almost surely, 2^{1001263540523} is an apocalyptic number.

1001263540523 is a deficient number, since it is larger than the sum of its proper divisors (25084717).

1001263540523 is an equidigital number, since it uses as much as digits as its factorization.

1001263540523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25084716.

The product of its (nonzero) digits is 21600, while the sum is 32.

The spelling of 1001263540523 in words is "one trillion, one billion, two hundred sixty-three million, five hundred forty thousand, five hundred twenty-three".