1838385621 has 6 divisors (see below), whose sum is σ = 2655445910. Its totient is φ = 1225590408.

The previous prime is 1838385617. The next prime is 1838385629. The reversal of 1838385621 is 1265838381.

1838385621 is a `hidden beast` number, since 1 + 8 + 3 + 83 + 8 + 562 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1271279025 + 567106596 = 35655^2 + 23814^2 .

It is not a de Polignac number, because 1838385621 - 2² = 1838385617 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 (1838385629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 102132526 + ... + 102132543.

Almost surely, 2^1838385621 is an apocalyptic number.

It is an amenable number.

1838385621 is a deficient number, since it is larger than the sum of its proper divisors (817060289).

1838385621 is a wasteful number, since it uses less digits than its factorization.

1838385621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204265075 (or 204265072 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 1838385621 is about 42876.3993474266. The cubic root of 1838385621 is about 1225.0266540917.

The spelling of 1838385621 in words is "one billion, eight hundred thirty-eight million, three hundred eighty-five thousand, six hundred twenty-one".