261120019 has 2 divisors, whose sum is σ = 261120020. Its totient is φ = 261120018.

The previous prime is 261119993. The next prime is 261120053. The reversal of 261120019 is 910021162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261120019 - 2⁷ = 261119891 is a prime.

It is a super-2 number, since 2×261120019² = 136367328645120722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (261121019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130560009 + 130560010.

It is an arithmetic number, because the mean of its divisors is an integer number (130560010).

Almost surely, 2^261120019 is an apocalyptic number.

261120019 is a deficient number, since it is larger than the sum of its proper divisors (1).

261120019 is an equidigital number, since it uses as much as digits as its factorization.

261120019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 261120019 is about 16159.2084892794. The cubic root of 261120019 is about 639.1655947390.

The spelling of 261120019 in words is "two hundred sixty-one million, one hundred twenty thousand, nineteen".