1772820 has 144 divisors (see below), whose sum is σ = 6511680. Its totient is φ = 399168.

The previous prime is 1772819. The next prime is 1772851. The reversal of 1772820 is 282771.

1772820 = T₉₁ + T₉₂ + ... + T₂₂₄.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 26427 + ... + 26493.

It is an arithmetic number, because the mean of its divisors is an integer number (45220).

2^1772820 is an apocalyptic number.

1772820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1772820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3255840).

1772820 is an abundant number, since it is smaller than the sum of its proper divisors (4738860).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1772820 is a wasteful number, since it uses less digits than its factorization.

1772820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99 (or 84 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 27.

The square root of 1772820 is about 1331.4728686684. The cubic root of 1772820 is about 121.0286570105.

The spelling of 1772820 in words is "one million, seven hundred seventy-two thousand, eight hundred twenty".