1978990741723 has 2 divisors, whose sum is σ = 1978990741724. Its totient is φ = 1978990741722.

The previous prime is 1978990741697. The next prime is 1978990741727. The reversal of 1978990741723 is 3271470998791.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1978990741723 - 2³³ = 1970400807131 is a prime.

It is not a weakly prime, because it can be changed into another prime (1978990741727) 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 as a sum of consecutive naturals, namely, 989495370861 + 989495370862.

It is an arithmetic number, because the mean of its divisors is an integer number (989495370862).

Almost surely, 2^{1978990741723} is an apocalyptic number.

1978990741723 is a deficient number, since it is larger than the sum of its proper divisors (1).

1978990741723 is an equidigital number, since it uses as much as digits as its factorization.

1978990741723 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48009024, while the sum is 67.

The spelling of 1978990741723 in words is "one trillion, nine hundred seventy-eight billion, nine hundred ninety million, seven hundred forty-one thousand, seven hundred twenty-three".