135291973 has 2 divisors, whose sum is σ = 135291974. Its totient is φ = 135291972.

The previous prime is 135291907. The next prime is 135292013. The reversal of 135291973 is 379192531.

It is an a-pointer prime, because the next prime (135292013) can be obtained adding 135291973 to its sum of digits (40).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73307844 + 61984129 = 8562^2 + 7873^2 .

It is a cyclic number.

It is not a de Polignac number, because 135291973 - 2⁹ = 135291461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (135297973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67645986 + 67645987.

It is an arithmetic number, because the mean of its divisors is an integer number (67645987).

Almost surely, 2^135291973 is an apocalyptic number.

It is an amenable number.

135291973 is a deficient number, since it is larger than the sum of its proper divisors (1).

135291973 is an equidigital number, since it uses as much as digits as its factorization.

135291973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51030, while the sum is 40.

The square root of 135291973 is about 11631.5077698465. The cubic root of 135291973 is about 513.3623449712.

The spelling of 135291973 in words is "one hundred thirty-five million, two hundred ninety-one thousand, nine hundred seventy-three".