307687681 has 4 divisors (see below), whose sum is σ = 351643072. Its totient is φ = 263732292.

The previous prime is 307687673. The next prime is 307687687. The reversal of 307687681 is 186786703.

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 not a de Polignac number, because 307687681 - 2³ = 307687673 is a prime.

It is a super-2 number, since 2×307687681² = 189343418078315522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (307687687) 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, 21977685 + ... + 21977698.

It is an arithmetic number, because the mean of its divisors is an integer number (87910768).

Almost surely, 2^307687681 is an apocalyptic number.

It is an amenable number.

307687681 is a deficient number, since it is larger than the sum of its proper divisors (43955391).

307687681 is an equidigital number, since it uses as much as digits as its factorization.

307687681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43955390.

The product of its (nonzero) digits is 338688, while the sum is 46.

The square root of 307687681 is about 17541.0285046231. The cubic root of 307687681 is about 675.1029973602.

The spelling of 307687681 in words is "three hundred seven million, six hundred eighty-seven thousand, six hundred eighty-one".