1221841 has 8 divisors (see below), whose sum is σ = 1326024. Its totient is φ = 1121280.

The previous prime is 1221823. The next prime is 1221853. The reversal of 1221841 is 1481221.

1221841 = T₁₃₀ + T₁₃₁ + ... + T₂₁₁.

1221841 = 33³ + 34³ + ... + 49³.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 3025 + 1218816 = 55^2 + 1104^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1221841 - 2¹¹ = 1219793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221811) 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, 180 + ... + 1573.

It is an arithmetic number, because the mean of its divisors is an integer number (165753).

2^1221841 is an apocalyptic number.

It is an amenable number.

1221841 is a deficient number, since it is larger than the sum of its proper divisors (104183).

1221841 is a wasteful number, since it uses less digits than its factorization.

1221841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1811.

The product of its digits is 128, while the sum is 19.

The square root of 1221841 is about 1105.3691691014. The cubic root of 1221841 is about 106.9066936315.

The spelling of 1221841 in words is "one million, two hundred twenty-one thousand, eight hundred forty-one".