1689891841 has 4 divisors (see below), whose sum is σ = 1843518384. Its totient is φ = 1536265300.

The previous prime is 1689891829. The next prime is 1689891899. The reversal of 1689891841 is 1481989861.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1689891841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1689891821) 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 in 3 ways as a sum of consecutive naturals, for example, 76813255 + ... + 76813276.

It is an arithmetic number, because the mean of its divisors is an integer number (460879596).

Almost surely, 2^1689891841 is an apocalyptic number.

1689891841 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1689891841 is a deficient number, since it is larger than the sum of its proper divisors (153626543).

1689891841 is a wasteful number, since it uses less digits than its factorization.

1689891841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153626542.

The product of its digits is 995328, while the sum is 55.

The square root of 1689891841 is about 41108.2940657965. The cubic root of 1689891841 is about 1191.1130139362.

The spelling of 1689891841 in words is "one billion, six hundred eighty-nine million, eight hundred ninety-one thousand, eight hundred forty-one".