1978990741727 has 2 divisors, whose sum is σ = 1978990741728. Its totient is φ = 1978990741726.

The previous prime is 1978990741723. The next prime is 1978990741729. The reversal of 1978990741727 is 7271470998791.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1978990741727 - 2² = 1978990741723 is a prime.

Together with 1978990741729, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1978990741723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 989495370863 + 989495370864.

It is an arithmetic number, because the mean of its divisors is an integer number (989495370864).

Almost surely, 2^{1978990741727} is an apocalyptic number.

1978990741727 is a deficient number, since it is larger than the sum of its proper divisors (1).

1978990741727 is an equidigital number, since it uses as much as digits as its factorization.

1978990741727 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112021056, while the sum is 71.

The spelling of 1978990741727 in words is "one trillion, nine hundred seventy-eight billion, nine hundred ninety million, seven hundred forty-one thousand, seven hundred twenty-seven".