261650172559 has 2 divisors, whose sum is σ = 261650172560. Its totient is φ = 261650172558.

The previous prime is 261650172527. The next prime is 261650172569. The reversal of 261650172559 is 955271056162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261650172559 - 2⁵ = 261650172527 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261650172569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130825086279 + 130825086280.

It is an arithmetic number, because the mean of its divisors is an integer number (130825086280).

Almost surely, 2^261650172559 is an apocalyptic number.

261650172559 is a deficient number, since it is larger than the sum of its proper divisors (1).

261650172559 is an equidigital number, since it uses as much as digits as its factorization.

261650172559 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1134000, while the sum is 49.

The spelling of 261650172559 in words is "two hundred sixty-one billion, six hundred fifty million, one hundred seventy-two thousand, five hundred fifty-nine".