8155021 has 6 divisors (see below), whose sum is σ = 9486510. Its totient is φ = 6989976.

The previous prime is 8155013. The next prime is 8155027. The reversal of 8155021 is 1205518.

8155021 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 7645225 + 509796 = 2765^2 + 714^2 .

It is not a de Polignac number, because 8155021 - 2³ = 8155013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 8154983 and 8155001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8155027) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 83166 + ... + 83263.

It is an arithmetic number, because the mean of its divisors is an integer number (1581085).

Almost surely, 2^8155021 is an apocalyptic number.

It is an amenable number.

8155021 is a deficient number, since it is larger than the sum of its proper divisors (1331489).

8155021 is a wasteful number, since it uses less digits than its factorization.

8155021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166443 (or 166436 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 22.

The square root of 8155021 is about 2855.6997391182. The cubic root of 8155021 is about 201.2835860770.

The spelling of 8155021 in words is "eight million, one hundred fifty-five thousand, twenty-one".