261590401 has 4 divisors (see below), whose sum is σ = 261781204. Its totient is φ = 261399600.

The previous prime is 261590383. The next prime is 261590419. The reversal of 261590401 is 104095162.

261590401 is nontrivially palindromic in base 5.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (261590383) and next prime (261590419).

It can be written as a sum of positive squares in 2 ways, for example, as 212576400 + 49014001 = 14580^2 + 7001^2 .

It is a cyclic number.

It is not a de Polignac number, because 261590401 - 2²⁷ = 127372673 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 261590401.

It is not an unprimeable number, because it can be changed into a prime (261590471) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 93330 + ... + 96091.

It is an arithmetic number, because the mean of its divisors is an integer number (65445301).

Almost surely, 2^261590401 is an apocalyptic number.

It is an amenable number.

261590401 is a deficient number, since it is larger than the sum of its proper divisors (190803).

261590401 is a wasteful number, since it uses less digits than its factorization.

261590401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190802.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 261590401 is about 16173.7565518960. The cubic root of 261590401 is about 639.5491624699.

The spelling of 261590401 in words is "two hundred sixty-one million, five hundred ninety thousand, four hundred one".