261266401 has 8 divisors (see below), whose sum is σ = 287786304. Its totient is φ = 235207920.

The previous prime is 261266381. The next prime is 261266437. The reversal of 261266401 is 104662162.

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 261266401 - 2⁹ = 261265889 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 261266401.

It is not an unprimeable number, because it can be changed into a prime (261266471) 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, 114166 + ... + 116431.

It is an arithmetic number, because the mean of its divisors is an integer number (35973288).

Almost surely, 2^261266401 is an apocalyptic number.

It is an amenable number.

261266401 is a deficient number, since it is larger than the sum of its proper divisors (26519903).

261266401 is a wasteful number, since it uses less digits than its factorization.

261266401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230711.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 261266401 is about 16163.7372225609. The cubic root of 261266401 is about 639.2850096354.

It can be divided in two parts, 261 and 266401, that added together give a palindrome (266662).

The spelling of 261266401 in words is "two hundred sixty-one million, two hundred sixty-six thousand, four hundred one".