1213539 has 4 divisors (see below), whose sum is σ = 1618056. Its totient is φ = 809024.

The previous prime is 1213529. The next prime is 1213547. The reversal of 1213539 is 9353121.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1213539 - 2⁹ = 1213027 is a prime.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (1213529) 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, 202254 + ... + 202259.

It is an arithmetic number, because the mean of its divisors is an integer number (404514).

2^1213539 is an apocalyptic number.

1213539 is a deficient number, since it is larger than the sum of its proper divisors (404517).

1213539 is an equidigital number, since it uses as much as digits as its factorization.

1213539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404516.

The product of its digits is 810, while the sum is 24.

The square root of 1213539 is about 1101.6074618484. The cubic root of 1213539 is about 106.6640114356.

The spelling of 1213539 in words is "one million, two hundred thirteen thousand, five hundred thirty-nine".