1808749440 has 640 divisors, whose sum is σ = 7091219520. Its totient is φ = 437944320.

The previous prime is 1808749381. The next prime is 1808749469. The reversal of 1808749440 is 449478081.

1808749440 is a `hidden beast` number, since 1 + 80 + 87 + 494 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 44115820 + ... + 44115860.

Almost surely, 2^1808749440 is an apocalyptic number.

1808749440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1808749440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3545609760).

1808749440 is an abundant number, since it is smaller than the sum of its proper divisors (5282470080).

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

1808749440 is a wasteful number, since it uses less digits than its factorization.

1808749440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 45.

The square root of 1808749440 is about 42529.3950109803. The cubic root of 1808749440 is about 1218.4081720640.

The spelling of 1808749440 in words is "one billion, eight hundred eight million, seven hundred forty-nine thousand, four hundred forty".