7621 has 2 divisors, whose sum is σ = 7622. Its totient is φ = 7620.

The previous prime is 7607. The next prime is 7639. The reversal of 7621 is 1267.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7396 + 225 = 86^2 + 15^2 .

It is a cyclic number.

It is not a de Polignac number, because 7621 - 2⁵ = 7589 is a prime.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 7595 and 7604.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3810 + 3811.

It is an arithmetic number, because the mean of its divisors is an integer number (3811).

2⁷⁶²¹ is an apocalyptic number.

It is an amenable number.

7621 is a deficient number, since it is larger than the sum of its proper divisors (1).

7621 is an equidigital number, since it uses as much as digits as its factorization.

7621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 84, while the sum is 16.

The square root of 7621 is about 87.2983390449. The cubic root of 7621 is about 19.6790435673.

Adding to 7621 its reverse (1267), we get a palindrome (8888).

It can be divided in two parts, 76 and 21, that multiplied together give a triangular number (1596 = T₅₆).

The spelling of 7621 in words is "seven thousand, six hundred twenty-one".