261635723123 has 8 divisors (see below), whose sum is σ = 284902784400. Its totient is φ = 239318337888.

The previous prime is 261635723113. The next prime is 261635723177. The reversal of 261635723123 is 321327536162.

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

It is a cyclic number.

It is not a de Polignac number, because 261635723123 - 2⁸ = 261635722867 is a prime.

It is a super-2 number, since 2×261635723123² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261635723113) 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 7 ways as a sum of consecutive naturals, for example, 237418436 + ... + 237419537.

It is an arithmetic number, because the mean of its divisors is an integer number (35612848050).

Almost surely, 2^261635723123 is an apocalyptic number.

261635723123 is a deficient number, since it is larger than the sum of its proper divisors (23267061277).

261635723123 is a wasteful number, since it uses less digits than its factorization.

261635723123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474838021.

The product of its digits is 272160, while the sum is 41.

The spelling of 261635723123 in words is "two hundred sixty-one billion, six hundred thirty-five million, seven hundred twenty-three thousand, one hundred twenty-three".