261609976 has 8 divisors (see below), whose sum is σ = 490518720. Its totient is φ = 130804984.

The previous prime is 261609973. The next prime is 261609989. The reversal of 261609976 is 679906162.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261609973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16350616 + ... + 16350631.

It is an arithmetic number, because the mean of its divisors is an integer number (61314840).

Almost surely, 2^261609976 is an apocalyptic number.

It is an amenable number.

261609976 is a deficient number, since it is larger than the sum of its proper divisors (228908744).

261609976 is a wasteful number, since it uses less digits than its factorization.

261609976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32701253 (or 32701249 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 46.

The square root of 261609976 is about 16174.3616875597. The cubic root of 261609976 is about 639.5651147150.

The spelling of 261609976 in words is "two hundred sixty-one million, six hundred nine thousand, nine hundred seventy-six".