1213936931665 has 16 divisors (see below), whose sum is σ = 1473555927888. Its totient is φ = 959974557696.

The previous prime is 1213936931513. The next prime is 1213936931671. The reversal of 1213936931665 is 5661396393121.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 91489915729 + 1122447015936 = 302473^2 + 1059456^2 .

It is a cyclic number.

It is not a de Polignac number, because 1213936931665 - 2¹³ = 1213936923473 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2669364 + ... + 3090853.

It is an arithmetic number, because the mean of its divisors is an integer number (92097245493).

Almost surely, 2^{1213936931665} is an apocalyptic number.

It is an amenable number.

1213936931665 is a deficient number, since it is larger than the sum of its proper divisors (259618996223).

1213936931665 is a wasteful number, since it uses less digits than its factorization.

1213936931665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5760708.

The product of its digits is 4723920, while the sum is 55.

The spelling of 1213936931665 in words is "one trillion, two hundred thirteen billion, nine hundred thirty-six million, nine hundred thirty-one thousand, six hundred sixty-five".