2167621 has 2 divisors, whose sum is σ = 2167622. Its totient is φ = 2167620.

The previous prime is 2167609. The next prime is 2167643. The reversal of 2167621 is 1267612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1718721 + 448900 = 1311^2 + 670^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2167621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2167661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1083810 + 1083811.

It is an arithmetic number, because the mean of its divisors is an integer number (1083811).

2^2167621 is an apocalyptic number.

It is an amenable number.

2167621 is a deficient number, since it is larger than the sum of its proper divisors (1).

2167621 is an equidigital number, since it uses as much as digits as its factorization.

2167621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1008, while the sum is 25.

The square root of 2167621 is about 1472.2842796145. The cubic root of 2167621 is about 129.4179302402.

Subtracting from 2167621 its reverse (1267612), we obtain a palindrome (900009).

The spelling of 2167621 in words is "two million, one hundred sixty-seven thousand, six hundred twenty-one".