1681887373 has 2 divisors, whose sum is σ = 1681887374. Its totient is φ = 1681887372.

The previous prime is 1681887359. The next prime is 1681887409. The reversal of 1681887373 is 3737881861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 870663049 + 811224324 = 29507^2 + 28482^2 .

It is a cyclic number.

It is not a de Polignac number, because 1681887373 - 2⁵ = 1681887341 is a prime.

It is a super-2 number, since 2×1681887373² = 5657490270913682258, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1681887373.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1681887343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840943686 + 840943687.

It is an arithmetic number, because the mean of its divisors is an integer number (840943687).

Almost surely, 2^1681887373 is an apocalyptic number.

It is an amenable number.

1681887373 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681887373 is an equidigital number, since it uses as much as digits as its factorization.

1681887373 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1354752, while the sum is 52.

The square root of 1681887373 is about 41010.8201941878. The cubic root of 1681887373 is about 1189.2293984644.

It can be divided in two parts, 168188 and 7373, that added together give a square (175561 = 419²).

The spelling of 1681887373 in words is "one billion, six hundred eighty-one million, eight hundred eighty-seven thousand, three hundred seventy-three".