261557471 has 8 divisors (see below), whose sum is σ = 299550720. Its totient is φ = 223721208.

The previous prime is 261557437. The next prime is 261557503. The reversal of 261557471 is 174755162.

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 261557471 - 2⁶ = 261557407 is a prime.

It is a super-3 number, since 3×261557471³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261559471) 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, 35651 + ... + 42356.

It is an arithmetic number, because the mean of its divisors is an integer number (37443840).

Almost surely, 2^261557471 is an apocalyptic number.

261557471 is a deficient number, since it is larger than the sum of its proper divisors (37993249).

261557471 is an equidigital number, since it uses as much as digits as its factorization.

261557471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78493.

The product of its digits is 58800, while the sum is 38.

The square root of 261557471 is about 16172.7385126948. The cubic root of 261557471 is about 639.5223250457.

The spelling of 261557471 in words is "two hundred sixty-one million, five hundred fifty-seven thousand, four hundred seventy-one".