386720731 has 4 divisors (see below), whose sum is σ = 389036592. Its totient is φ = 384404872.

The previous prime is 386720693. The next prime is 386720749. The reversal of 386720731 is 137027683.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 386720731 - 2¹⁷ = 386589659 is a prime.

It is a super-2 number, since 2×386720731² = 299105847570348722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (386720431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1157680 + ... + 1158013.

It is an arithmetic number, because the mean of its divisors is an integer number (97259148).

Almost surely, 2^386720731 is an apocalyptic number.

386720731 is a deficient number, since it is larger than the sum of its proper divisors (2315861).

386720731 is a wasteful number, since it uses less digits than its factorization.

386720731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2315860.

The product of its (nonzero) digits is 42336, while the sum is 37.

The square root of 386720731 is about 19665.2162713762. The cubic root of 386720731 is about 728.5608294407.

The spelling of 386720731 in words is "three hundred eighty-six million, seven hundred twenty thousand, seven hundred thirty-one".