261553043 has 2 divisors, whose sum is σ = 261553044. Its totient is φ = 261553042.

The previous prime is 261553013. The next prime is 261553057. The reversal of 261553043 is 340355162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261553043 - 2²⁴ = 244775827 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261552997 and 261553015.

It is not a weakly prime, because it can be changed into another prime (261553013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130776521 + 130776522.

It is an arithmetic number, because the mean of its divisors is an integer number (130776522).

Almost surely, 2^261553043 is an apocalyptic number.

261553043 is a deficient number, since it is larger than the sum of its proper divisors (1).

261553043 is an equidigital number, since it uses as much as digits as its factorization.

261553043 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10800, while the sum is 29.

The square root of 261553043 is about 16172.6016150773. The cubic root of 261553043 is about 639.5187161246.

The spelling of 261553043 in words is "two hundred sixty-one million, five hundred fifty-three thousand, forty-three".