1577782081973 has 2 divisors, whose sum is σ = 1577782081974. Its totient is φ = 1577782081972.

The previous prime is 1577782081961. The next prime is 1577782081991. The reversal of 1577782081973 is 3791802877751.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 834769113649 + 743012968324 = 913657^2 + 861982^2 .

It is a cyclic number.

It is not a de Polignac number, because 1577782081973 - 2⁸ = 1577782081717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1577782081903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 788891040986 + 788891040987.

It is an arithmetic number, because the mean of its divisors is an integer number (788891040987).

Almost surely, 2^{1577782081973} is an apocalyptic number.

It is an amenable number.

1577782081973 is a deficient number, since it is larger than the sum of its proper divisors (1).

1577782081973 is an equidigital number, since it uses as much as digits as its factorization.

1577782081973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 41489280, while the sum is 65.

The spelling of 1577782081973 in words is "one trillion, five hundred seventy-seven billion, seven hundred eighty-two million, eighty-one thousand, nine hundred seventy-three".