386640439 has 2 divisors, whose sum is σ = 386640440. Its totient is φ = 386640438.

The previous prime is 386640427. The next prime is 386640479. The reversal of 386640439 is 934046683.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 386640439 - 2⁵ = 386640407 is a prime.

It is a super-2 number, since 2×386640439² = 298981658140225442, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 386640395 and 386640404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (386640479) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 193320219 + 193320220.

It is an arithmetic number, because the mean of its divisors is an integer number (193320220).

Almost surely, 2^386640439 is an apocalyptic number.

386640439 is a deficient number, since it is larger than the sum of its proper divisors (1).

386640439 is an equidigital number, since it uses as much as digits as its factorization.

386640439 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 373248, while the sum is 43.

The square root of 386640439 is about 19663.1746928109. The cubic root of 386640439 is about 728.5104040300.

The spelling of 386640439 in words is "three hundred eighty-six million, six hundred forty thousand, four hundred thirty-nine".