261251109983 has 4 divisors (see below), whose sum is σ = 261253805208. Its totient is φ = 261248414760.

The previous prime is 261251109937. The next prime is 261251110019. The reversal of 261251109983 is 389901152162.

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 261251109983 - 2⁶ = 261251109919 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261251109583) 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, 1196573 + ... + 1397958.

It is an arithmetic number, because the mean of its divisors is an integer number (65313451302).

Almost surely, 2^261251109983 is an apocalyptic number.

261251109983 is a deficient number, since it is larger than the sum of its proper divisors (2695225).

261251109983 is a wasteful number, since it uses less digits than its factorization.

261251109983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2695224.

The product of its (nonzero) digits is 233280, while the sum is 47.

The spelling of 261251109983 in words is "two hundred sixty-one billion, two hundred fifty-one million, one hundred nine thousand, nine hundred eighty-three".