261541191249 has 16 divisors (see below), whose sum is σ = 417273696000. Its totient is φ = 160948425168.

The previous prime is 261541191229. The next prime is 261541191253. The reversal of 261541191249 is 942191145162.

261541191249 is a `hidden beast` number, since 2 + 61 + 541 + 1 + 9 + 1 + 2 + 49 = 666.

It is not a de Polignac number, because 261541191249 - 2¹¹ = 261541189201 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261541191229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 372565449 + ... + 372566150.

It is an arithmetic number, because the mean of its divisors is an integer number (26079606000).

Almost surely, 2^261541191249 is an apocalyptic number.

It is an amenable number.

261541191249 is a deficient number, since it is larger than the sum of its proper divisors (155732504751).

261541191249 is a wasteful number, since it uses less digits than its factorization.

261541191249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 745131621 (or 745131615 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The spelling of 261541191249 in words is "two hundred sixty-one billion, five hundred forty-one million, one hundred ninety-one thousand, two hundred forty-nine".