1625132440721 has 2 divisors, whose sum is σ = 1625132440722. Its totient is φ = 1625132440720.

The previous prime is 1625132440709. The next prime is 1625132440753. The reversal of 1625132440721 is 1270442315261.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1609064343121 + 16068097600 = 1268489^2 + 126760^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1625132440721 is a prime.

It is not a weakly prime, because it can be changed into another prime (1625132440021) 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, 812566220360 + 812566220361.

It is an arithmetic number, because the mean of its divisors is an integer number (812566220361).

Almost surely, 2^{1625132440721} is an apocalyptic number.

It is an amenable number.

1625132440721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1625132440721 is an equidigital number, since it uses as much as digits as its factorization.

1625132440721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 80640, while the sum is 38.

Adding to 1625132440721 its reverse (1270442315261), we get a palindrome (2895574755982).

The spelling of 1625132440721 in words is "one trillion, six hundred twenty-five billion, one hundred thirty-two million, four hundred forty thousand, seven hundred twenty-one".