1261872800965 has 64 divisors (see below), whose sum is σ = 1748469219840. Its totient is φ = 856396800000.

The previous prime is 1261872800939. The next prime is 1261872801023. The reversal of 1261872800965 is 5690082781621.

It is a happy number.

It is not a de Polignac number, because 1261872800965 - 2²⁵ = 1261839246533 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1779792031 + ... + 1779792739.

It is an arithmetic number, because the mean of its divisors is an integer number (27319831560).

Almost surely, 2^{1261872800965} is an apocalyptic number.

It is an amenable number.

1261872800965 is a deficient number, since it is larger than the sum of its proper divisors (486596418875).

1261872800965 is a wasteful number, since it uses less digits than its factorization.

1261872800965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1934.

The product of its (nonzero) digits is 2903040, while the sum is 55.

The spelling of 1261872800965 in words is "one trillion, two hundred sixty-one billion, eight hundred seventy-two million, eight hundred thousand, nine hundred sixty-five".