1820722 has 4 divisors (see below), whose sum is σ = 2731086. Its totient is φ = 910360.

The previous prime is 1820711. The next prime is 1820737. The reversal of 1820722 is 2270281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2270281 = 13 ⋅174637.

It can be written as a sum of positive squares in only one way, i.e., 1661521 + 159201 = 1289^2 + 399^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 1820693 and 1820702.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 455179 + ... + 455182.

2^1820722 is an apocalyptic number.

1820722 is a deficient number, since it is larger than the sum of its proper divisors (910364).

1820722 is an equidigital number, since it uses as much as digits as its factorization.

1820722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 910363.

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 1820722 is about 1349.3413207932. The cubic root of 1820722 is about 122.1090577275.

The spelling of 1820722 in words is "one million, eight hundred twenty thousand, seven hundred twenty-two".