135254021 has 4 divisors (see below), whose sum is σ = 154576032. Its totient is φ = 115932012.

The previous prime is 135253991. The next prime is 135254029. The reversal of 135254021 is 120452531.

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, and also an emirpimes, since its reverse is a distinct semiprime: 120452531 = 17 ⋅7085443.

It is not a de Polignac number, because 135254021 - 2¹⁴ = 135237637 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 (135254029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9660995 + ... + 9661008.

It is an arithmetic number, because the mean of its divisors is an integer number (38644008).

Almost surely, 2^135254021 is an apocalyptic number.

It is an amenable number.

135254021 is a deficient number, since it is larger than the sum of its proper divisors (19322011).

135254021 is an equidigital number, since it uses as much as digits as its factorization.

135254021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19322010.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 135254021 is about 11629.8762246208. The cubic root of 135254021 is about 513.3143378121.

The spelling of 135254021 in words is "one hundred thirty-five million, two hundred fifty-four thousand, twenty-one".