1622561 has 4 divisors (see below), whose sum is σ = 1666452. Its totient is φ = 1578672.

The previous prime is 1622557. The next prime is 1622573. The reversal of 1622561 is 1652261.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 846400 + 776161 = 920^2 + 881^2 .

It is a cyclic number.

It is not a de Polignac number, because 1622561 - 2² = 1622557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1622591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21890 + ... + 21963.

It is an arithmetic number, because the mean of its divisors is an integer number (416613).

2^1622561 is an apocalyptic number.

It is an amenable number.

1622561 is a deficient number, since it is larger than the sum of its proper divisors (43891).

1622561 is an equidigital number, since it uses as much as digits as its factorization.

1622561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43890.

The product of its digits is 720, while the sum is 23.

The square root of 1622561 is about 1273.7978646551. The cubic root of 1622561 is about 117.5078853920.

The spelling of 1622561 in words is "one million, six hundred twenty-two thousand, five hundred sixty-one".