1820012646641 has 4 divisors (see below), whose sum is σ = 2080014453312. Its totient is φ = 1560010839972.

The previous prime is 1820012646601. The next prime is 1820012646653. The reversal of 1820012646641 is 1466462100281.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1820012646641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1820012646601) by changing a digit.

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, 130000903325 + ... + 130000903338.

It is an arithmetic number, because the mean of its divisors is an integer number (520003613328).

Almost surely, 2^{1820012646641} is an apocalyptic number.

It is an amenable number.

1820012646641 is a deficient number, since it is larger than the sum of its proper divisors (260001806671).

1820012646641 is an equidigital number, since it uses as much as digits as its factorization.

1820012646641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260001806670.

The product of its (nonzero) digits is 110592, while the sum is 41.

The spelling of 1820012646641 in words is "one trillion, eight hundred twenty billion, twelve million, six hundred forty-six thousand, six hundred forty-one".