261646992 has 60 divisors (see below), whose sum is σ = 733395520. Its totient is φ = 87079104.

The previous prime is 261646969. The next prime is 261647021. The reversal of 261646992 is 299646162.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 138309 + ... + 140187.

Almost surely, 2^261646992 is an apocalyptic number.

It is an amenable number.

261646992 is an abundant number, since it is smaller than the sum of its proper divisors (471748528).

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

261646992 is a wasteful number, since it uses less digits than its factorization.

261646992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2860 (or 2851 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 261646992 is about 16175.5059271727. The cubic root of 261646992 is about 639.5952779707.

The spelling of 261646992 in words is "two hundred sixty-one million, six hundred forty-six thousand, nine hundred ninety-two".