1221579 has 6 divisors (see below), whose sum is σ = 1764516. Its totient is φ = 814380.

The previous prime is 1221559. The next prime is 1221589. The reversal of 1221579 is 9751221.

It is not a de Polignac number, because 1221579 - 2¹² = 1217483 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221559) 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 5 ways as a sum of consecutive naturals, for example, 67857 + ... + 67874.

It is an arithmetic number, because the mean of its divisors is an integer number (294086).

2^1221579 is an apocalyptic number.

1221579 is a deficient number, since it is larger than the sum of its proper divisors (542937).

1221579 is a wasteful number, since it uses less digits than its factorization.

1221579 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135737 (or 135734 counting only the distinct ones).

The product of its digits is 1260, while the sum is 27.

The square root of 1221579 is about 1105.2506503052. The cubic root of 1221579 is about 106.8990517326.

The spelling of 1221579 in words is "one million, two hundred twenty-one thousand, five hundred seventy-nine".