261089401 has 2 divisors, whose sum is σ = 261089402. Its totient is φ = 261089400.

The previous prime is 261089377. The next prime is 261089443. The reversal of 261089401 is 104980162.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 237314025 + 23775376 = 15405^2 + 4876^2 .

It is a cyclic number.

It is not a de Polignac number, because 261089401 - 2⁹ = 261088889 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (261089461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130544700 + 130544701.

It is an arithmetic number, because the mean of its divisors is an integer number (130544701).

Almost surely, 2^261089401 is an apocalyptic number.

It is an amenable number.

261089401 is a deficient number, since it is larger than the sum of its proper divisors (1).

261089401 is an equidigital number, since it uses as much as digits as its factorization.

261089401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 261089401 is about 16158.2610759945. The cubic root of 261089401 is about 639.1406116715.

The spelling of 261089401 in words is "two hundred sixty-one million, eighty-nine thousand, four hundred one".