1221585 has 8 divisors (see below), whose sum is σ = 1954560. Its totient is φ = 651504.

The previous prime is 1221559. The next prime is 1221589. The reversal of 1221585 is 5851221.

1221585 = 345² + 346² + ... + 354².

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1221585 - 2⁷ = 1221457 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221589) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40705 + ... + 40734.

It is an arithmetic number, because the mean of its divisors is an integer number (244320).

2^1221585 is an apocalyptic number.

1221585 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1221585 is a deficient number, since it is larger than the sum of its proper divisors (732975).

1221585 is an equidigital number, since it uses as much as digits as its factorization.

1221585 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81447.

The product of its digits is 800, while the sum is 24.

The square root of 1221585 is about 1105.2533646183. The cubic root of 1221585 is about 106.8992267502.

The spelling of 1221585 in words is "one million, two hundred twenty-one thousand, five hundred eighty-five".