1720661200361 has 2 divisors, whose sum is σ = 1720661200362. Its totient is φ = 1720661200360.

The previous prime is 1720661200261. The next prime is 1720661200367. The reversal of 1720661200361 is 1630021660271.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1600366683136 + 120294517225 = 1265056^2 + 346835^2 .

It is a cyclic number.

It is not a de Polignac number, because 1720661200361 - 2¹⁴ = 1720661183977 is a prime.

It is not a weakly prime, because it can be changed into another prime (1720661200367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 860330600180 + 860330600181.

It is an arithmetic number, because the mean of its divisors is an integer number (860330600181).

Almost surely, 2^{1720661200361} is an apocalyptic number.

It is an amenable number.

1720661200361 is a deficient number, since it is larger than the sum of its proper divisors (1).

1720661200361 is an equidigital number, since it uses as much as digits as its factorization.

1720661200361 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 35.

The spelling of 1720661200361 in words is "one trillion, seven hundred twenty billion, six hundred sixty-one million, two hundred thousand, three hundred sixty-one".