261623610663361 has 32 divisors (see below), whose sum is σ = 270918922095360. Its totient is φ = 252478656460800.

The previous prime is 261623610663353. The next prime is 261623610663379. The reversal of 261623610663361 is 163366016326162.

It is a cyclic number.

It is not a de Polignac number, because 261623610663361 - 2³ = 261623610663353 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261623610663299 and 261623610663308.

It is not an unprimeable number, because it can be changed into a prime (261623610663341) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 47386994281 + ... + 47386999801.

It is an arithmetic number, because the mean of its divisors is an integer number (8466216315480).

Almost surely, 2^{261623610663361} is an apocalyptic number.

It is an amenable number.

261623610663361 is a deficient number, since it is larger than the sum of its proper divisors (9295311431999).

261623610663361 is a wasteful number, since it uses less digits than its factorization.

261623610663361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12697.

The product of its (nonzero) digits is 5038848, while the sum is 52.

The spelling of 261623610663361 in words is "two hundred sixty-one trillion, six hundred twenty-three billion, six hundred ten million, six hundred sixty-three thousand, three hundred sixty-one".