261440447 has 2 divisors, whose sum is σ = 261440448. Its totient is φ = 261440446.

The previous prime is 261440441. The next prime is 261440503. The reversal of 261440447 is 744044162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261440447 - 2⁶ = 261440383 is a prime.

It is a super-2 number, since 2×261440447² = 136702214655119618, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261440441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130720223 + 130720224.

It is an arithmetic number, because the mean of its divisors is an integer number (130720224).

Almost surely, 2^261440447 is an apocalyptic number.

261440447 is a deficient number, since it is larger than the sum of its proper divisors (1).

261440447 is an equidigital number, since it uses as much as digits as its factorization.

261440447 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21504, while the sum is 32.

The square root of 261440447 is about 16169.1201677766. The cubic root of 261440447 is about 639.4269341240.

The spelling of 261440447 in words is "two hundred sixty-one million, four hundred forty thousand, four hundred forty-seven".