1697948561 has 2 divisors, whose sum is σ = 1697948562. Its totient is φ = 1697948560.

The previous prime is 1697948557. The next prime is 1697948591. The reversal of 1697948561 is 1658497961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1594804225 + 103144336 = 39935^2 + 10156^2 .

It is a cyclic number.

It is not a de Polignac number, because 1697948561 - 2² = 1697948557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1697948497 and 1697948506.

It is not a weakly prime, because it can be changed into another prime (1697948591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 848974280 + 848974281.

It is an arithmetic number, because the mean of its divisors is an integer number (848974281).

Almost surely, 2^1697948561 is an apocalyptic number.

It is an amenable number.

1697948561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1697948561 is an equidigital number, since it uses as much as digits as its factorization.

1697948561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3265920, while the sum is 56.

The square root of 1697948561 is about 41206.1713945860. The cubic root of 1697948561 is about 1193.0029285036.

The spelling of 1697948561 in words is "one billion, six hundred ninety-seven million, nine hundred forty-eight thousand, five hundred sixty-one".