1221590 has 16 divisors (see below), whose sum is σ = 2216160. Its totient is φ = 484800.

The previous prime is 1221589. The next prime is 1221593. The reversal of 1221590 is 951221.

1221590 = T₄₄ + T₄₅ + ... + T₁₉₄.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221593) 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 7 ways as a sum of consecutive naturals, for example, 1106 + ... + 1914.

It is an arithmetic number, because the mean of its divisors is an integer number (138510).

2^1221590 is an apocalyptic number.

1221590 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221590 is a deficient number, since it is larger than the sum of its proper divisors (994570).

1221590 is a wasteful number, since it uses less digits than its factorization.

1221590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 967.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 1221590 is about 1105.2556265408. The cubic root of 1221590 is about 106.8993725977.

The spelling of 1221590 in words is "one million, two hundred twenty-one thousand, five hundred ninety".