681680065 has 16 divisors (see below), whose sum is σ = 894934656. Its totient is φ = 494348800.

The previous prime is 681680009. The next prime is 681680089. The reversal of 681680065 is 560086186.

It is a happy number.

It is not a de Polignac number, because 681680065 - 2¹⁷ = 681548993 is a prime.

It is a super-2 number, since 2×681680065² = 929375422036808450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1860 + ... + 36970.

It is an arithmetic number, because the mean of its divisors is an integer number (55933416).

Almost surely, 2^681680065 is an apocalyptic number.

It is an amenable number.

681680065 is a deficient number, since it is larger than the sum of its proper divisors (213254591).

681680065 is a wasteful number, since it uses less digits than its factorization.

681680065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35480.

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 681680065 is about 26109.0035236889. The cubic root of 681680065 is about 880.0895505459.

The spelling of 681680065 in words is "six hundred eighty-one million, six hundred eighty thousand, sixty-five".