1261872800964 has 36 divisors (see below), whose sum is σ = 3213016767324. Its totient is φ = 417554015232.

The previous prime is 1261872800939. The next prime is 1261872801023. The reversal of 1261872800964 is 4690082781621.

It is a happy number.

1261872800964 is a `hidden beast` number, since 12 + 618 + 7 + 2 + 8 + 0 + 0 + 9 + 6 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 922925276100 + 338947524864 = 960690^2 + 582192^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 1261872800964.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 127922157 + ... + 127932020.

It is an arithmetic number, because the mean of its divisors is an integer number (89250465759).

Almost surely, 2^{1261872800964} is an apocalyptic number.

It is an amenable number.

1261872800964 is an abundant number, since it is smaller than the sum of its proper divisors (1951143966360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261872800964 is a wasteful number, since it uses less digits than its factorization.

1261872800964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255854324 (or 255854319 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 54.

The spelling of 1261872800964 in words is "one trillion, two hundred sixty-one billion, eight hundred seventy-two million, eight hundred thousand, nine hundred sixty-four".