1215213 has 4 divisors (see below), whose sum is σ = 1620288. Its totient is φ = 810140.

The previous prime is 1215209. The next prime is 1215229. The reversal of 1215213 is 3125121.

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 1215213 - 2² = 1215209 is a prime.

It is an Ulam number.

It is a D-number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1215192 and 1215201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 202533 + ... + 202538.

It is an arithmetic number, because the mean of its divisors is an integer number (405072).

2^1215213 is an apocalyptic number.

It is an amenable number.

1215213 is a deficient number, since it is larger than the sum of its proper divisors (405075).

1215213 is an equidigital number, since it uses as much as digits as its factorization.

1215213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405074.

The product of its digits is 60, while the sum is 15.

The square root of 1215213 is about 1102.3669987804. The cubic root of 1215213 is about 106.7130343117.

It can be divided in two parts, 12 and 15213, that added together give a triangular number (15225 = T₁₇₄).

The spelling of 1215213 in words is "one million, two hundred fifteen thousand, two hundred thirteen".