123437521 has 2 divisors, whose sum is σ = 123437522. Its totient is φ = 123437520.

The previous prime is 123437491. The next prime is 123437537. The reversal of 123437521 is 125734321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 117483921 + 5953600 = 10839^2 + 2440^2 .

It is an emirp because it is prime and its reverse (125734321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 123437521 - 2²¹ = 121340369 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 123437521.

It is not a weakly prime, because it can be changed into another prime (123432521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61718760 + 61718761.

It is an arithmetic number, because the mean of its divisors is an integer number (61718761).

Almost surely, 2^123437521 is an apocalyptic number.

It is an amenable number.

123437521 is a deficient number, since it is larger than the sum of its proper divisors (1).

123437521 is an equidigital number, since it uses as much as digits as its factorization.

123437521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5040, while the sum is 28.

The square root of 123437521 is about 11110.2439667183. The cubic root of 123437521 is about 497.9079535583.

The spelling of 123437521 in words is "one hundred twenty-three million, four hundred thirty-seven thousand, five hundred twenty-one".