1865809940 has 12 divisors (see below), whose sum is σ = 3918200916. Its totient is φ = 746323968.

The previous prime is 1865809873. The next prime is 1865809949. The reversal of 1865809940 is 499085681.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 361456144 + 1504353796 = 19012^2 + 38786^2 .

It is a hoax number, since the sum of its digits (50) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1865809949) 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, 46645229 + ... + 46645268.

It is an arithmetic number, because the mean of its divisors is an integer number (326516743).

Almost surely, 2^1865809940 is an apocalyptic number.

1865809940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1865809940 is an abundant number, since it is smaller than the sum of its proper divisors (2052390976).

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

1865809940 is a wasteful number, since it uses less digits than its factorization.

1865809940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93290506 (or 93290504 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 50.

The square root of 1865809940 is about 43195.0221669118. The cubic root of 1865809940 is about 1231.0881022925.

The spelling of 1865809940 in words is "one billion, eight hundred sixty-five million, eight hundred nine thousand, nine hundred forty".