681929186 has 8 divisors (see below), whose sum is σ = 1029409500. Its totient is φ = 338792688.

The previous prime is 681929173. The next prime is 681929191.

It is a happy number.

681929186 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 2 ways, for example, as 676260025 + 5669161 = 26005^2 + 2381^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-4 number, since 4×681929186⁴ (a number of 36 digits) contains 4444 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1085561 + ... + 1086188.

Almost surely, 2^681929186 is an apocalyptic number.

681929186 is a deficient number, since it is larger than the sum of its proper divisors (347480314).

681929186 is a wasteful number, since it uses less digits than its factorization.

681929186 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2171908.

The product of its digits is 373248, while the sum is 50.

The square root of 681929186 is about 26113.7738751028. The cubic root of 681929186 is about 880.1967475031.

The spelling of 681929186 in words is "six hundred eighty-one million, nine hundred twenty-nine thousand, one hundred eighty-six".