1681719461 has 2 divisors, whose sum is σ = 1681719462. Its totient is φ = 1681719460.

The previous prime is 1681719433. The next prime is 1681719467. The reversal of 1681719461 is 1649171861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1598800225 + 82919236 = 39985^2 + 9106^2 .

It is a cyclic number.

It is not a de Polignac number, because 1681719461 - 2²⁶ = 1614610597 is a prime.

It is a super-2 number, since 2×1681719461² = 5656360691012261042, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1681719467) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840859730 + 840859731.

It is an arithmetic number, because the mean of its divisors is an integer number (840859731).

Almost surely, 2^1681719461 is an apocalyptic number.

It is an amenable number.

1681719461 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681719461 is an equidigital number, since it uses as much as digits as its factorization.

1681719461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 44.

The square root of 1681719461 is about 41008.7729760353. The cubic root of 1681719461 is about 1189.1898213925.

The spelling of 1681719461 in words is "one billion, six hundred eighty-one million, seven hundred nineteen thousand, four hundred sixty-one".