1642820 has 12 divisors (see below), whose sum is σ = 3449964. Its totient is φ = 657120.

The previous prime is 1642813. The next prime is 1642831. The reversal of 1642820 is 282461.

It can be written as a sum of positive squares in 2 ways, for example, as 334084 + 1308736 = 578^2 + 1144^2 .

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is a plaindrome in base 13.

It is an unprimeable number.

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, 41051 + ... + 41090.

It is an arithmetic number, because the mean of its divisors is an integer number (287497).

2^1642820 is an apocalyptic number.

1642820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1642820 is an abundant number, since it is smaller than the sum of its proper divisors (1807144).

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

1642820 is a wasteful number, since it uses less digits than its factorization.

1642820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82150 (or 82148 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 1642820 is about 1281.7253996079. The cubic root of 1642820 is about 117.9949246117.

The spelling of 1642820 in words is "one million, six hundred forty-two thousand, eight hundred twenty".