8212509 has 20 divisors (see below), whose sum is σ = 12506076. Its totient is φ = 5368896.

The previous prime is 8212493. The next prime is 8212511. The reversal of 8212509 is 9052128.

It can be written as a sum of positive squares in 2 ways, for example, as 6579225 + 1633284 = 2565^2 + 1278^2 .

It is not a de Polignac number, because 8212509 - 2⁴ = 8212493 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8212549) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3337 + ... + 5249.

Almost surely, 2^8212509 is an apocalyptic number.

It is an amenable number.

8212509 is a deficient number, since it is larger than the sum of its proper divisors (4293567).

8212509 is a wasteful number, since it uses less digits than its factorization.

8212509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1978 (or 1969 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 8212509 is about 2865.7475464528. The cubic root of 8212509 is about 201.7554551392.

The spelling of 8212509 in words is "eight million, two hundred twelve thousand, five hundred nine".