1221629 has 8 divisors (see below), whose sum is σ = 1269048. Its totient is φ = 1175040.

The previous prime is 1221601. The next prime is 1221631. The reversal of 1221629 is 9261221.

It can be written as a sum of positive squares in 4 ways, for example, as 624100 + 597529 = 790^2 + 773^2 .

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 1221629 - 2⁸ = 1221373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4949 + ... + 5189.

It is an arithmetic number, because the mean of its divisors is an integer number (158631).

2^1221629 is an apocalyptic number.

It is an amenable number.

1221629 is a deficient number, since it is larger than the sum of its proper divisors (47419).

1221629 is a wasteful number, since it uses less digits than its factorization.

1221629 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415.

The product of its digits is 432, while the sum is 23.

The square root of 1221629 is about 1105.2732693773. The cubic root of 1221629 is about 106.9005101947.

The spelling of 1221629 in words is "one million, two hundred twenty-one thousand, six hundred twenty-nine".