261544501263013 has 4 divisors (see below), whose sum is σ = 261600590588128. Its totient is φ = 261488411937900.

The previous prime is 261544501262981. The next prime is 261544501263107. The reversal of 261544501263013 is 310362105445162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 261544501263013 - 2⁵ = 261544501262981 is a prime.

It is a super-2 number, since 2×261544501263013² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261544501243013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28044655563 + ... + 28044664888.

It is an arithmetic number, because the mean of its divisors is an integer number (65400147647032).

Almost surely, 2^{261544501263013} is an apocalyptic number.

It is an amenable number.

261544501263013 is a deficient number, since it is larger than the sum of its proper divisors (56089325115).

261544501263013 is an equidigital number, since it uses as much as digits as its factorization.

261544501263013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56089325114.

The product of its (nonzero) digits is 518400, while the sum is 43.

The spelling of 261544501263013 in words is "two hundred sixty-one trillion, five hundred forty-four billion, five hundred one million, two hundred sixty-three thousand, thirteen".