1648648581761 has 2 divisors, whose sum is σ = 1648648581762. Its totient is φ = 1648648581760.

The previous prime is 1648648581733. The next prime is 1648648581809. The reversal of 1648648581761 is 1671858468461.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1644470252161 + 4178329600 = 1282369^2 + 64640^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1648648581761 is a prime.

It is a super-2 number, since 2×1648648581761² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1648648581721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 824324290880 + 824324290881.

It is an arithmetic number, because the mean of its divisors is an integer number (824324290881).

Almost surely, 2^{1648648581761} is an apocalyptic number.

It is an amenable number.

1648648581761 is a deficient number, since it is larger than the sum of its proper divisors (1).

1648648581761 is an equidigital number, since it uses as much as digits as its factorization.

1648648581761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 61931520, while the sum is 65.

The spelling of 1648648581761 in words is "one trillion, six hundred forty-eight billion, six hundred forty-eight million, five hundred eighty-one thousand, seven hundred sixty-one".