1231728786 has 48 divisors (see below), whose sum is σ = 2693422368. Its totient is φ = 406800000.

The previous prime is 1231728769. The next prime is 1231728787. The reversal of 1231728786 is 6878271321.

It is a super-2 number, since 2×1231728786² = 3034311604522067592, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1231728787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1024986 + ... + 1026186.

It is an arithmetic number, because the mean of its divisors is an integer number (56112966).

Almost surely, 2^1231728786 is an apocalyptic number.

1231728786 is an abundant number, since it is smaller than the sum of its proper divisors (1461693582).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1231728786 is a wasteful number, since it uses less digits than its factorization.

1231728786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1687 (or 1684 counting only the distinct ones).

The product of its digits is 225792, while the sum is 45.

The square root of 1231728786 is about 35095.9938739452. The cubic root of 1231728786 is about 1071.9430110280.

The spelling of 1231728786 in words is "one billion, two hundred thirty-one million, seven hundred twenty-eight thousand, seven hundred eighty-six".