855506121 has 4 divisors (see below), whose sum is σ = 1140674832. Its totient is φ = 570337412.

The previous prime is 855506117. The next prime is 855506129. The reversal of 855506121 is 121605558.

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 855506121 - 2² = 855506117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (855506129) 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, 142584351 + ... + 142584356.

It is an arithmetic number, because the mean of its divisors is an integer number (285168708).

Almost surely, 2^855506121 is an apocalyptic number.

It is an amenable number.

855506121 is a deficient number, since it is larger than the sum of its proper divisors (285168711).

855506121 is a wasteful number, since it uses less digits than its factorization.

855506121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285168710.

The product of its (nonzero) digits is 12000, while the sum is 33.

The square root of 855506121 is about 29249.0362405328. The cubic root of 855506121 is about 949.3092378376.

The spelling of 855506121 in words is "eight hundred fifty-five million, five hundred six thousand, one hundred twenty-one".