1682743981 has 2 divisors, whose sum is σ = 1682743982. Its totient is φ = 1682743980.

The previous prime is 1682743973. The next prime is 1682744047. The reversal of 1682743981 is 1893472861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1138455081 + 544288900 = 33741^2 + 23330^2 .

It is a cyclic number.

It is not a de Polignac number, because 1682743981 - 2³ = 1682743973 is a prime.

It is a super-2 number, since 2×1682743981² = 5663254611183456722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1682743081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 841371990 + 841371991.

It is an arithmetic number, because the mean of its divisors is an integer number (841371991).

Almost surely, 2^1682743981 is an apocalyptic number.

It is an amenable number.

1682743981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1682743981 is an equidigital number, since it uses as much as digits as its factorization.

1682743981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 580608, while the sum is 49.

The square root of 1682743981 is about 41021.2625476106. The cubic root of 1682743981 is about 1189.4312610733.

The spelling of 1682743981 in words is "one billion, six hundred eighty-two million, seven hundred forty-three thousand, nine hundred eighty-one".