123521537 has 2 divisors, whose sum is σ = 123521538. Its totient is φ = 123521536.

The previous prime is 123521533. The next prime is 123521539. The reversal of 123521537 is 735125321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75759616 + 47761921 = 8704^2 + 6911^2 .

It is a cyclic number.

It is not a de Polignac number, because 123521537 - 2² = 123521533 is a prime.

Together with 123521539, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (123521533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61760768 + 61760769.

It is an arithmetic number, because the mean of its divisors is an integer number (61760769).

Almost surely, 2^123521537 is an apocalyptic number.

It is an amenable number.

123521537 is a deficient number, since it is larger than the sum of its proper divisors (1).

123521537 is an equidigital number, since it uses as much as digits as its factorization.

123521537 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6300, while the sum is 29.

The square root of 123521537 is about 11114.0243386453. The cubic root of 123521537 is about 498.0208926037.

Adding to 123521537 its reverse (735125321), we get a palindrome (858646858).

The spelling of 123521537 in words is "one hundred twenty-three million, five hundred twenty-one thousand, five hundred thirty-seven".