3658639 has 2 divisors, whose sum is σ = 3658640. Its totient is φ = 3658638.

The previous prime is 3658637. The next prime is 3658661. The reversal of 3658639 is 9368563.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3658639 - 2¹ = 3658637 is a prime.

Together with 3658637, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3658631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1829319 + 1829320.

It is an arithmetic number, because the mean of its divisors is an integer number (1829320).

Almost surely, 2^3658639 is an apocalyptic number.

3658639 is a deficient number, since it is larger than the sum of its proper divisors (1).

3658639 is an equidigital number, since it uses as much as digits as its factorization.

3658639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116640, while the sum is 40.

The square root of 3658639 is about 1912.7569108488. The cubic root of 3658639 is about 154.0895498738.

The spelling of 3658639 in words is "three million, six hundred fifty-eight thousand, six hundred thirty-nine".