1215979 has 4 divisors (see below), whose sum is σ = 1238976. Its totient is φ = 1192984.

The previous prime is 1215923. The next prime is 1216009. The reversal of 1215979 is 9795121.

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 1215979 - 2¹¹ = 1213931 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1215919) 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, 11419 + ... + 11524.

It is an arithmetic number, because the mean of its divisors is an integer number (309744).

2^1215979 is an apocalyptic number.

1215979 is a deficient number, since it is larger than the sum of its proper divisors (22997).

1215979 is an equidigital number, since it uses as much as digits as its factorization.

1215979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22996.

The product of its digits is 5670, while the sum is 34.

The square root of 1215979 is about 1102.7143782503. The cubic root of 1215979 is about 106.7354515108.

The spelling of 1215979 in words is "one million, two hundred fifteen thousand, nine hundred seventy-nine".