261040663 has 8 divisors (see below), whose sum is σ = 281258208. Its totient is φ = 240842784.

The previous prime is 261040657. The next prime is 261040667. The reversal of 261040663 is 366040162.

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

It is not a de Polignac number, because 261040663 - 2²¹ = 258943511 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 (261040667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34281 + ... + 41197.

It is an arithmetic number, because the mean of its divisors is an integer number (35157276).

Almost surely, 2^261040663 is an apocalyptic number.

261040663 is a deficient number, since it is larger than the sum of its proper divisors (20217545).

261040663 is a wasteful number, since it uses less digits than its factorization.

261040663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9833.

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 261040663 is about 16156.7528606462. The cubic root of 261040663 is about 639.1008393770.

The spelling of 261040663 in words is "two hundred sixty-one million, forty thousand, six hundred sixty-three".