1945991548777 has 2 divisors, whose sum is σ = 1945991548778. Its totient is φ = 1945991548776.

The previous prime is 1945991548769. The next prime is 1945991548801. The reversal of 1945991548777 is 7778451995491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1326652454416 + 619339094361 = 1151804^2 + 786981^2 .

It is a cyclic number.

It is not a de Polignac number, because 1945991548777 - 2³ = 1945991548769 is a prime.

It is not a weakly prime, because it can be changed into another prime (1945991548877) 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, 972995774388 + 972995774389.

It is an arithmetic number, because the mean of its divisors is an integer number (972995774389).

Almost surely, 2^{1945991548777} is an apocalyptic number.

It is an amenable number.

1945991548777 is a deficient number, since it is larger than the sum of its proper divisors (1).

1945991548777 is an equidigital number, since it uses as much as digits as its factorization.

1945991548777 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 800150400, while the sum is 76.

The spelling of 1945991548777 in words is "one trillion, nine hundred forty-five billion, nine hundred ninety-one million, five hundred forty-eight thousand, seven hundred seventy-seven".