261359489 has 2 divisors, whose sum is σ = 261359490. Its totient is φ = 261359488.

The previous prime is 261359477. The next prime is 261359503. The reversal of 261359489 is 984953162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 131217025 + 130142464 = 11455^2 + 11408^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261359489 is a prime.

It is a super-2 number, since 2×261359489² = 136617564980682242, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (261355489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130679744 + 130679745.

It is an arithmetic number, because the mean of its divisors is an integer number (130679745).

Almost surely, 2^261359489 is an apocalyptic number.

It is an amenable number.

261359489 is a deficient number, since it is larger than the sum of its proper divisors (1).

261359489 is an equidigital number, since it uses as much as digits as its factorization.

261359489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 466560, while the sum is 47.

The square root of 261359489 is about 16166.6164982039. The cubic root of 261359489 is about 639.3609253756.

The spelling of 261359489 in words is "two hundred sixty-one million, three hundred fifty-nine thousand, four hundred eighty-nine".