1261008654849 has 48 divisors (see below), whose sum is σ = 2031302707200. Its totient is φ = 749136342528.

The previous prime is 1261008654847. The next prime is 1261008654881. The reversal of 1261008654849 is 9484568001621.

1261008654849 is a `hidden beast` number, since 1 + 2 + 6 + 10 + 0 + 86 + 548 + 4 + 9 = 666.

It is not a de Polignac number, because 1261008654849 - 2¹ = 1261008654847 is a prime.

It is a super-2 number, since 2×1261008654849² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1261008654795 and 1261008654804.

It is not an unprimeable number, because it can be changed into a prime (1261008654847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4841152 + ... + 5094974.

It is an arithmetic number, because the mean of its divisors is an integer number (42318806400).

Almost surely, 2^{1261008654849} is an apocalyptic number.

1261008654849 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1261008654849 is a deficient number, since it is larger than the sum of its proper divisors (770294052351).

1261008654849 is a wasteful number, since it uses less digits than its factorization.

1261008654849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255574 (or 255571 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 54.

The spelling of 1261008654849 in words is "one trillion, two hundred sixty-one billion, eight million, six hundred fifty-four thousand, eight hundred forty-nine".