123550621 has 2 divisors, whose sum is σ = 123550622. Its totient is φ = 123550620.

The previous prime is 123550619. The next prime is 123550631. The reversal of 123550621 is 126055321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 123543225 + 7396 = 11115^2 + 86^2 .

It is a cyclic number.

It is not a de Polignac number, because 123550621 - 2¹ = 123550619 is a prime.

Together with 123550619, 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 (123550631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61775310 + 61775311.

It is an arithmetic number, because the mean of its divisors is an integer number (61775311).

Almost surely, 2^123550621 is an apocalyptic number.

It is an amenable number.

123550621 is a deficient number, since it is larger than the sum of its proper divisors (1).

123550621 is an equidigital number, since it uses as much as digits as its factorization.

123550621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 123550621 is about 11115.3326985745. The cubic root of 123550621 is about 498.0599770239.

The spelling of 123550621 in words is "one hundred twenty-three million, five hundred fifty thousand, six hundred twenty-one".