12280345891 has 4 divisors (see below), whose sum is σ = 13396740984. Its totient is φ = 11163950800.

The previous prime is 12280345873. The next prime is 12280345897. The reversal of 12280345891 is 19854308221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19854308221 = 11 ⋅1804937111.

It is a cyclic number.

It is not a de Polignac number, because 12280345891 - 2¹⁷ = 12280214819 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12280345897) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 558197530 + ... + 558197551.

It is an arithmetic number, because the mean of its divisors is an integer number (3349185246).

Almost surely, 2^12280345891 is an apocalyptic number.

12280345891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12280345891 is a deficient number, since it is larger than the sum of its proper divisors (1116395093).

12280345891 is a wasteful number, since it uses less digits than its factorization.

12280345891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1116395092.

The product of its (nonzero) digits is 138240, while the sum is 43.

The spelling of 12280345891 in words is "twelve billion, two hundred eighty million, three hundred forty-five thousand, eight hundred ninety-one".