3123203221991 has 2 divisors, whose sum is σ = 3123203221992. Its totient is φ = 3123203221990.

The previous prime is 3123203221973. The next prime is 3123203222039. The reversal of 3123203221991 is 1991223023213.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3123203221991 - 2¹⁸ = 3123202959847 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3123203223991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1561601610995 + 1561601610996.

It is an arithmetic number, because the mean of its divisors is an integer number (1561601610996).

Almost surely, 2^{3123203221991} is an apocalyptic number.

3123203221991 is a deficient number, since it is larger than the sum of its proper divisors (1).

3123203221991 is an equidigital number, since it uses as much as digits as its factorization.

3123203221991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34992, while the sum is 38.

The spelling of 3123203221991 in words is "three trillion, one hundred twenty-three billion, two hundred three million, two hundred twenty-one thousand, nine hundred ninety-one".