12811921042 has 8 divisors (see below), whose sum is σ = 19241639100. Its totient is φ = 6398041344.

The previous prime is 12811921037. The next prime is 12811921061. The reversal of 12811921042 is 24012911821.

It can be written as a sum of positive squares in 2 ways, for example, as 9065134521 + 3746786521 = 95211^2 + 61211^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 12811920995 and 12811921013.

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 3 ways as a sum of consecutive naturals, for example, 3957567 + ... + 3960802.

Almost surely, 2^12811921042 is an apocalyptic number.

12811921042 is a deficient number, since it is larger than the sum of its proper divisors (6429718058).

12811921042 is an equidigital number, since it uses as much as digits as its factorization.

12811921042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7919180.

The product of its (nonzero) digits is 2304, while the sum is 31.

The spelling of 12811921042 in words is "twelve billion, eight hundred eleven million, nine hundred twenty-one thousand, forty-two".