1972540782577 has 2 divisors, whose sum is σ = 1972540782578. Its totient is φ = 1972540782576.

The previous prime is 1972540782539. The next prime is 1972540782599. The reversal of 1972540782577 is 7752870452791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1090971894016 + 881568888561 = 1044496^2 + 938919^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1972540782577 is a prime.

It is not a weakly prime, because it can be changed into another prime (1972540780577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 986270391288 + 986270391289.

It is an arithmetic number, because the mean of its divisors is an integer number (986270391289).

Almost surely, 2^{1972540782577} is an apocalyptic number.

It is an amenable number.

1972540782577 is a deficient number, since it is larger than the sum of its proper divisors (1).

1972540782577 is an equidigital number, since it uses as much as digits as its factorization.

1972540782577 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69148800, while the sum is 64.

The spelling of 1972540782577 in words is "one trillion, nine hundred seventy-two billion, five hundred forty million, seven hundred eighty-two thousand, five hundred seventy-seven".