261009276 has 24 divisors (see below), whose sum is σ = 664387584. Its totient is φ = 79093680.

The previous prime is 261009263. The next prime is 261009293. The reversal of 261009276 is 672900162.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 988540 + ... + 988803.

It is an arithmetic number, because the mean of its divisors is an integer number (27682816).

Almost surely, 2^261009276 is an apocalyptic number.

It is an amenable number.

261009276 is an abundant number, since it is smaller than the sum of its proper divisors (403378308).

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

261009276 is a wasteful number, since it uses less digits than its factorization.

261009276 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1977361 (or 1977359 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 261009276 is about 16155.7815038456. The cubic root of 261009276 is about 639.0752236207.

The spelling of 261009276 in words is "two hundred sixty-one million, nine thousand, two hundred seventy-six".