1321200012 has 24 divisors (see below), whose sum is σ = 3363054912. Its totient is φ = 400363600.

The previous prime is 1321199977. The next prime is 1321200047. The reversal of 1321200012 is 2100021231.

It is an interprime number because it is at equal distance from previous prime (1321199977) and next prime (1321200047).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5004414 + ... + 5004677.

It is an arithmetic number, because the mean of its divisors is an integer number (140127288).

Almost surely, 2^1321200012 is an apocalyptic number.

1321200012 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1321200012 is an abundant number, since it is smaller than the sum of its proper divisors (2041854900).

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

1321200012 is a wasteful number, since it uses less digits than its factorization.

1321200012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10009109 (or 10009107 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 1321200012 is about 36348.3151191359. The cubic root of 1321200012 is about 1097.2936256467.

Adding to 1321200012 its reverse (2100021231), we get a palindrome (3421221243).

The spelling of 1321200012 in words is "one billion, three hundred twenty-one million, two hundred thousand, twelve".