261045401 has 8 divisors (see below), whose sum is σ = 268417800. Its totient is φ = 253720960.

The previous prime is 261045383. The next prime is 261045461. The reversal of 261045401 is 104540162.

It can be written as a sum of positive squares in 4 ways, for example, as 13801225 + 247244176 = 3715^2 + 15724^2 .

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 261045401 - 2¹⁴ = 261029017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261045461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 806 + ... + 22863.

It is an arithmetic number, because the mean of its divisors is an integer number (33552225).

Almost surely, 2^261045401 is an apocalyptic number.

It is an amenable number.

261045401 is a deficient number, since it is larger than the sum of its proper divisors (7372399).

261045401 is a wasteful number, since it uses less digits than its factorization.

261045401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23979.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 261045401 is about 16156.8994859781. The cubic root of 261045401 is about 639.1047060051.

Adding to 261045401 its reverse (104540162), we get a palindrome (365585563).

The spelling of 261045401 in words is "two hundred sixty-one million, forty-five thousand, four hundred one".