12129785 has 4 divisors (see below), whose sum is σ = 14555748. Its totient is φ = 9703824.

The previous prime is 12129781. The next prime is 12129811. The reversal of 12129785 is 58792121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2808976 + 9320809 = 1676^2 + 3053^2 .

It is a cyclic number.

It is not a de Polignac number, because 12129785 - 2² = 12129781 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12129781) 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, 1212974 + ... + 1212983.

It is an arithmetic number, because the mean of its divisors is an integer number (3638937).

Almost surely, 2^12129785 is an apocalyptic number.

It is an amenable number.

12129785 is a deficient number, since it is larger than the sum of its proper divisors (2425963).

12129785 is an equidigital number, since it uses as much as digits as its factorization.

12129785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2425962.

The product of its digits is 10080, while the sum is 35.

The square root of 12129785 is about 3482.7840874794. The cubic root of 12129785 is about 229.7652614520.

The spelling of 12129785 in words is "twelve million, one hundred twenty-nine thousand, seven hundred eighty-five".