681994869 has 4 divisors (see below), whose sum is σ = 909326496. Its totient is φ = 454663244.

The previous prime is 681994867. The next prime is 681994871. The reversal of 681994869 is 968499186.

681994869 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 an interprime number because it is at equal distance from previous prime (681994867) and next prime (681994871).

It is a cyclic number.

It is not a de Polignac number, because 681994869 - 2¹ = 681994867 is a prime.

It is a super-2 number, since 2×681994869² = 930234002684654322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681994867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113665809 + ... + 113665814.

It is an arithmetic number, because the mean of its divisors is an integer number (227331624).

Almost surely, 2^681994869 is an apocalyptic number.

It is an amenable number.

681994869 is a deficient number, since it is larger than the sum of its proper divisors (227331627).

681994869 is a wasteful number, since it uses less digits than its factorization.

681994869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227331626.

The product of its digits is 6718464, while the sum is 60.

The square root of 681994869 is about 26115.0314761442. The cubic root of 681994869 is about 880.2250065990.

The spelling of 681994869 in words is "six hundred eighty-one million, nine hundred ninety-four thousand, eight hundred sixty-nine".