261017771 has 8 divisors (see below), whose sum is σ = 299139840. Its totient is φ = 223104168.

The previous prime is 261017741. The next prime is 261017773. The reversal of 261017771 is 177710162.

It is a happy number.

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

It is not a de Polignac number, because 261017771 - 2⁶ = 261017707 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261017773) 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, 49421 + ... + 54446.

It is an arithmetic number, because the mean of its divisors is an integer number (37392480).

Almost surely, 2^261017771 is an apocalyptic number.

261017771 is a deficient number, since it is larger than the sum of its proper divisors (38122069).

261017771 is a wasteful number, since it uses less digits than its factorization.

261017771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104233.

The product of its (nonzero) digits is 4116, while the sum is 32.

The square root of 261017771 is about 16156.0444106842. The cubic root of 261017771 is about 639.0821568163.

The spelling of 261017771 in words is "two hundred sixty-one million, seventeen thousand, seven hundred seventy-one".