12261981065 has 16 divisors (see below), whose sum is σ = 14790433728. Its totient is φ = 9758995776.

The previous prime is 12261981029. The next prime is 12261981077. The reversal of 12261981065 is 56018916221.

It is a cyclic number.

It is not a de Polignac number, because 12261981065 - 2⁶ = 12261981001 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, 903107 + ... + 916583.

It is an arithmetic number, because the mean of its divisors is an integer number (924402108).

Almost surely, 2^12261981065 is an apocalyptic number.

It is an amenable number.

12261981065 is a deficient number, since it is larger than the sum of its proper divisors (2528452663).

12261981065 is a wasteful number, since it uses less digits than its factorization.

12261981065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14408.

The product of its (nonzero) digits is 51840, while the sum is 41.

The spelling of 12261981065 in words is "twelve billion, two hundred sixty-one million, nine hundred eighty-one thousand, sixty-five".