7639 has 2 divisors, whose sum is σ = 7640. Its totient is φ = 7638.

The previous prime is 7621. The next prime is 7643. The reversal of 7639 is 9367.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 7639 - 2⁵ = 7607 is a prime.

It is a d-powerful number, because it can be written as 7³ + 3⁸ + 6 + 9³ .

7639 is a lucky number.

It is a nialpdrome in base 6.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3819 + 3820.

It is an arithmetic number, because the mean of its divisors is an integer number (3820).

2⁷⁶³⁹ is an apocalyptic number.

7639 is a deficient number, since it is larger than the sum of its proper divisors (1).

7639 is an equidigital number, since it uses as much as digits as its factorization.

7639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1134, while the sum is 25.

The square root of 7639 is about 87.4013729869. The cubic root of 7639 is about 19.6945246621.

Subtracting 7639 from its reverse (9367), we obtain a cube (1728 = 12³).

It can be divided in two parts, 7 and 639, that added together give a palindrome (646).

The spelling of 7639 in words is "seven thousand, six hundred thirty-nine".