261565306476 has 12 divisors (see below), whose sum is σ = 610319048472. Its totient is φ = 87188435488.

The previous prime is 261565306427. The next prime is 261565306493. The reversal of 261565306476 is 674603565162.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10898554425 + ... + 10898554448.

It is an arithmetic number, because the mean of its divisors is an integer number (50859920706).

Almost surely, 2^261565306476 is an apocalyptic number.

It is an amenable number.

261565306476 is an abundant number, since it is smaller than the sum of its proper divisors (348753741996).

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

261565306476 is a wasteful number, since it uses less digits than its factorization.

261565306476 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21797108880 (or 21797108878 counting only the distinct ones).

The product of its (nonzero) digits is 5443200, while the sum is 51.

The spelling of 261565306476 in words is "two hundred sixty-one billion, five hundred sixty-five million, three hundred six thousand, four hundred seventy-six".