261623263 has 8 divisors (see below), whose sum is σ = 293121360. Its totient is φ = 231410880.

The previous prime is 261623261. The next prime is 261623269. The reversal of 261623263 is 362326162.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261623263 - 2¹ = 261623261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261623261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 320998 + ... + 321811.

It is an arithmetic number, because the mean of its divisors is an integer number (36640170).

Almost surely, 2^261623263 is an apocalyptic number.

261623263 is a deficient number, since it is larger than the sum of its proper divisors (31498097).

261623263 is a wasteful number, since it uses less digits than its factorization.

261623263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642857.

The product of its digits is 15552, while the sum is 31.

The square root of 261623263 is about 16174.7724249833. The cubic root of 261623263 is about 639.5759422300.

The spelling of 261623263 in words is "two hundred sixty-one million, six hundred twenty-three thousand, two hundred sixty-three".