261758752643 has 8 divisors (see below), whose sum is σ = 261907781520. Its totient is φ = 261609769440.

The previous prime is 261758752637. The next prime is 261758752649. The reversal of 261758752643 is 346257857162.

261758752643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (261758752637) and next prime (261758752649).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261758752643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261758752649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20473913 + ... + 20486693.

It is an arithmetic number, because the mean of its divisors is an integer number (32738472690).

Almost surely, 2^261758752643 is an apocalyptic number.

261758752643 is a deficient number, since it is larger than the sum of its proper divisors (149028877).

261758752643 is a wasteful number, since it uses less digits than its factorization.

261758752643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22837.

The product of its digits is 16934400, while the sum is 56.

The spelling of 261758752643 in words is "two hundred sixty-one billion, seven hundred fifty-eight million, seven hundred fifty-two thousand, six hundred forty-three".