1261655967969 has 12 divisors (see below), whose sum is σ = 1901626386816. Its totient is φ = 804534240312.

The previous prime is 1261655967937. The next prime is 1261655967989. The reversal of 1261655967969 is 9697695561621.

1261655967969 is a `hidden beast` number, since 1 + 2 + 6 + 1 + 6 + 559 + 6 + 7 + 9 + 69 = 666.

It is not a de Polignac number, because 1261655967969 - 2⁵ = 1261655967937 is a prime.

It is a super-2 number, since 2×1261655967969² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1261655967897 and 1261655967906.

It is not an unprimeable number, because it can be changed into a prime (1261655967989) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3047477977 + ... + 3047478390.

It is an arithmetic number, because the mean of its divisors is an integer number (158468865568).

Almost surely, 2^{1261655967969} is an apocalyptic number.

It is an amenable number.

1261655967969 is a deficient number, since it is larger than the sum of its proper divisors (639970418847).

1261655967969 is a wasteful number, since it uses less digits than its factorization.

1261655967969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6094956396 (or 6094956393 counting only the distinct ones).

The product of its digits is 330674400, while the sum is 72.

The spelling of 1261655967969 in words is "one trillion, two hundred sixty-one billion, six hundred fifty-five million, nine hundred sixty-seven thousand, nine hundred sixty-nine".