123613621 has 2 divisors, whose sum is σ = 123613622. Its totient is φ = 123613620.

The previous prime is 123613603. The next prime is 123613663. The reversal of 123613621 is 126316321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122434225 + 1179396 = 11065^2 + 1086^2 .

It is an emirp because it is prime and its reverse (126316321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 123613621 - 2¹⁷ = 123482549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123613121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61806810 + 61806811.

It is an arithmetic number, because the mean of its divisors is an integer number (61806811).

Almost surely, 2^123613621 is an apocalyptic number.

It is an amenable number.

123613621 is a deficient number, since it is larger than the sum of its proper divisors (1).

123613621 is an equidigital number, since it uses as much as digits as its factorization.

123613621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 25.

The square root of 123613621 is about 11118.1662606745. The cubic root of 123613621 is about 498.1446183002.

Adding to 123613621 its reverse (126316321), we get a palindrome (249929942).

The spelling of 123613621 in words is "one hundred twenty-three million, six hundred thirteen thousand, six hundred twenty-one".