135166021 has 4 divisors (see below), whose sum is σ = 135352672. Its totient is φ = 134979372.

The previous prime is 135165949. The next prime is 135166027. The reversal of 135166021 is 120661531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 135166021 - 2⁹ = 135165509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135166027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 92235 + ... + 93688.

It is an arithmetic number, because the mean of its divisors is an integer number (33838168).

Almost surely, 2^135166021 is an apocalyptic number.

It is an amenable number.

135166021 is a deficient number, since it is larger than the sum of its proper divisors (186651).

135166021 is an equidigital number, since it uses as much as digits as its factorization.

135166021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186650.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 135166021 is about 11626.0922497630. The cubic root of 135166021 is about 513.2029881665.

The spelling of 135166021 in words is "one hundred thirty-five million, one hundred sixty-six thousand, twenty-one".