1820925109 has 8 divisors (see below), whose sum is σ = 1886619960. Its totient is φ = 1755423936.

The previous prime is 1820925107. The next prime is 1820925121. The reversal of 1820925109 is 9015290281.

It can be written as a sum of positive squares in 4 ways, for example, as 534626884 + 1286298225 = 23122^2 + 35865^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1820925109 - 2¹ = 1820925107 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1820925101) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29142 + ... + 67015.

It is an arithmetic number, because the mean of its divisors is an integer number (235827495).

Almost surely, 2^1820925109 is an apocalyptic number.

It is an amenable number.

1820925109 is a deficient number, since it is larger than the sum of its proper divisors (65694851).

1820925109 is an equidigital number, since it uses as much as digits as its factorization.

1820925109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96839.

The product of its (nonzero) digits is 12960, while the sum is 37.

The square root of 1820925109 is about 42672.2990826602. The cubic root of 1820925109 is about 1221.1359814729.

The spelling of 1820925109 in words is "one billion, eight hundred twenty million, nine hundred twenty-five thousand, one hundred nine".