8212171215 has 32 divisors (see below), whose sum is σ = 13921203456. Its totient is φ = 4119575040.

The previous prime is 8212171213. The next prime is 8212171217. The reversal of 8212171215 is 5121712128.

It is an interprime number because it is at equal distance from previous prime (8212171213) and next prime (8212171217).

It is not a de Polignac number, because 8212171215 - 2¹ = 8212171213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8212171213) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 430020 + ... + 448710.

It is an arithmetic number, because the mean of its divisors is an integer number (435037608).

Almost surely, 2^8212171215 is an apocalyptic number.

8212171215 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

8212171215 is a deficient number, since it is larger than the sum of its proper divisors (5709032241).

8212171215 is a wasteful number, since it uses less digits than its factorization.

8212171215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20439.

The product of its digits is 2240, while the sum is 30.

The square root of 8212171215 is about 90621.0307544557. The cubic root of 8212171215 is about 2017.5268899708.

The spelling of 8212171215 in words is "eight billion, two hundred twelve million, one hundred seventy-one thousand, two hundred fifteen".