1898681 has 2 divisors, whose sum is σ = 1898682. Its totient is φ = 1898680.

The previous prime is 1898641. The next prime is 1898693. The reversal of 1898681 is 1868981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1585081 + 313600 = 1259^2 + 560^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1898681 is a prime.

It is a super-2 number, since 2×1898681² = 7209979079522, which contains 22 as substring.

It is a Chen prime.

1898681 is a strobogrammatic number because it is the same when read upside-down.

It is a plaindrome in base 15.

It is not a weakly prime, because it can be changed into another prime (1898621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 949340 + 949341.

It is an arithmetic number, because the mean of its divisors is an integer number (949341).

2^1898681 is an apocalyptic number.

It is an amenable number.

1898681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1898681 is an equidigital number, since it uses as much as digits as its factorization.

1898681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 41.

The square root of 1898681 is about 1377.9263405567. The cubic root of 1898681 is about 123.8275655614.

The spelling of 1898681 in words is "one million, eight hundred ninety-eight thousand, six hundred eighty-one".