261421726237166 has 16 divisors (see below), whose sum is σ = 433195956023040. Its totient is φ = 117323904754680.

The previous prime is 261421726237129. The next prime is 261421726237183. The reversal of 261421726237166 is 661732627124162.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75207629516 + ... + 75207632991.

It is an arithmetic number, because the mean of its divisors is an integer number (27074747251440).

Almost surely, 2^{261421726237166} is an apocalyptic number.

261421726237166 is a deficient number, since it is larger than the sum of its proper divisors (171774229785874).

261421726237166 is a wasteful number, since it uses less digits than its factorization.

261421726237166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150415262599.

The product of its digits is 12192768, while the sum is 56.

The spelling of 261421726237166 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, seven hundred twenty-six million, two hundred thirty-seven thousand, one hundred sixty-six".