1820404556 has 6 divisors (see below), whose sum is σ = 3185707980. Its totient is φ = 910202276.

The previous prime is 1820404549. The next prime is 1820404561. The reversal of 1820404556 is 6554040281.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 227550566 + ... + 227550573.

It is an arithmetic number, because the mean of its divisors is an integer number (530951330).

Almost surely, 2^1820404556 is an apocalyptic number.

It is an amenable number.

1820404556 is a deficient number, since it is larger than the sum of its proper divisors (1365303424).

1820404556 is a wasteful number, since it uses less digits than its factorization.

1820404556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 455101143 (or 455101141 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 35.

The square root of 1820404556 is about 42666.1992213977. The cubic root of 1820404556 is about 1221.0196071863.

The spelling of 1820404556 in words is "one billion, eight hundred twenty million, four hundred four thousand, five hundred fifty-six".