135208435021 has 4 divisors (see below), whose sum is σ = 147500110944. Its totient is φ = 122916759100.

The previous prime is 135208435013. The next prime is 135208435027. The reversal of 135208435021 is 120534802531.

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 135208435021 - 2³ = 135208435013 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 (135208435027) 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, 6145837945 + ... + 6145837966.

It is an arithmetic number, because the mean of its divisors is an integer number (36875027736).

Almost surely, 2^135208435021 is an apocalyptic number.

135208435021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

135208435021 is a deficient number, since it is larger than the sum of its proper divisors (12291675923).

135208435021 is a wasteful number, since it uses less digits than its factorization.

135208435021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12291675922.

The product of its (nonzero) digits is 28800, while the sum is 34.

The spelling of 135208435021 in words is "one hundred thirty-five billion, two hundred eight million, four hundred thirty-five thousand, twenty-one".