1728974981 has 2 divisors, whose sum is σ = 1728974982. Its totient is φ = 1728974980.

The previous prime is 1728974971. The next prime is 1728975007. The reversal of 1728974981 is 1894798271.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1359028225 + 369946756 = 36865^2 + 19234^2 .

It is a cyclic number.

It is not a de Polignac number, because 1728974981 - 2¹⁰ = 1728973957 is a prime.

It is a super-2 number, since 2×1728974981² = 5978708969847900722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1728974941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 864487490 + 864487491.

It is an arithmetic number, because the mean of its divisors is an integer number (864487491).

Almost surely, 2^1728974981 is an apocalyptic number.

It is an amenable number.

1728974981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1728974981 is an equidigital number, since it uses as much as digits as its factorization.

1728974981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2032128, while the sum is 56.

The square root of 1728974981 is about 41580.9449267330. The cubic root of 1728974981 is about 1200.2256476129.

The spelling of 1728974981 in words is "one billion, seven hundred twenty-eight million, nine hundred seventy-four thousand, nine hundred eighty-one".