261653790318 has 32 divisors (see below), whose sum is σ = 555055079040. Its totient is φ = 81996763680.

The previous prime is 261653790271. The next prime is 261653790323. The reversal of 261653790318 is 813097356162.

It is a super-2 number, since 2×261653790318² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8745405 + ... + 8775272.

It is an arithmetic number, because the mean of its divisors is an integer number (17345471220).

Almost surely, 2^261653790318 is an apocalyptic number.

261653790318 is an abundant number, since it is smaller than the sum of its proper divisors (293401288722).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261653790318 is a wasteful number, since it uses less digits than its factorization.

261653790318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17520832.

The product of its (nonzero) digits is 1632960, while the sum is 51.

The spelling of 261653790318 in words is "two hundred sixty-one billion, six hundred fifty-three million, seven hundred ninety thousand, three hundred eighteen".