1809021936 has 20 divisors (see below), whose sum is σ = 4673306792. Its totient is φ = 603007296.

The previous prime is 1809021923. The next prime is 1809021937. The reversal of 1809021936 is 6391209081.

It is a junction number, because it is equal to n+sod(n) for n = 1809021894 and 1809021903.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1809021937) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18843931 + ... + 18844026.

Almost surely, 2^1809021936 is an apocalyptic number.

1809021936 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1809021936 is an abundant number, since it is smaller than the sum of its proper divisors (2864284856).

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

1809021936 is a wasteful number, since it uses less digits than its factorization.

1809021936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37687968 (or 37687962 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 1809021936 is about 42532.5985098489. The cubic root of 1809021936 is about 1218.4693551618.

The spelling of 1809021936 in words is "one billion, eight hundred nine million, twenty-one thousand, nine hundred thirty-six".