1820861886 has 32 divisors (see below), whose sum is σ = 3690448128. Its totient is φ = 598881920.

The previous prime is 1820861873. The next prime is 1820861893. The reversal of 1820861886 is 6881680281.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 147991 + ... + 159821.

It is an arithmetic number, because the mean of its divisors is an integer number (115326504).

Almost surely, 2^1820861886 is an apocalyptic number.

1820861886 is an abundant number, since it is smaller than the sum of its proper divisors (1869586242).

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

1820861886 is a wasteful number, since it uses less digits than its factorization.

1820861886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12176.

The product of its (nonzero) digits is 294912, while the sum is 48.

The square root of 1820861886 is about 42671.5582794910. The cubic root of 1820861886 is about 1221.1218485882.

The spelling of 1820861886 in words is "one billion, eight hundred twenty million, eight hundred sixty-one thousand, eight hundred eighty-six".