135142232521 has 2 divisors, whose sum is σ = 135142232522. Its totient is φ = 135142232520.

The previous prime is 135142232431. The next prime is 135142232551. The reversal of 135142232521 is 125232241531.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 135082711296 + 59521225 = 367536^2 + 7715^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-135142232521 is a prime.

It is not a weakly prime, because it can be changed into another prime (135142232551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67571116260 + 67571116261.

It is an arithmetic number, because the mean of its divisors is an integer number (67571116261).

Almost surely, 2^135142232521 is an apocalyptic number.

It is an amenable number.

135142232521 is a deficient number, since it is larger than the sum of its proper divisors (1).

135142232521 is an equidigital number, since it uses as much as digits as its factorization.

135142232521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14400, while the sum is 31.

The spelling of 135142232521 in words is "one hundred thirty-five billion, one hundred forty-two million, two hundred thirty-two thousand, five hundred twenty-one".