261066751 has 8 divisors (see below), whose sum is σ = 285058944. Its totient is φ = 237117720.

The previous prime is 261066733. The next prime is 261066791. The reversal of 261066751 is 157660162.

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 261066751 - 2¹⁷ = 260935679 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261066791) 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, 2590 + ... + 22996.

It is an arithmetic number, because the mean of its divisors is an integer number (35632368).

Almost surely, 2^261066751 is an apocalyptic number.

261066751 is a deficient number, since it is larger than the sum of its proper divisors (23992193).

261066751 is a wasteful number, since it uses less digits than its factorization.

261066751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21581.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 261066751 is about 16157.5601809184. The cubic root of 261066751 is about 639.1221289175.

The spelling of 261066751 in words is "two hundred sixty-one million, sixty-six thousand, seven hundred fifty-one".