1808220720 has 40 divisors (see below), whose sum is σ = 5605484976. Its totient is φ = 482192128.

The previous prime is 1808220679. The next prime is 1808220721. The reversal of 1808220720 is 270228081.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (1808220721) 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, 3766887 + ... + 3767366.

Almost surely, 2^1808220720 is an apocalyptic number.

1808220720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1808220720 is an abundant number, since it is smaller than the sum of its proper divisors (3797264256).

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

1808220720 is a wasteful number, since it uses less digits than its factorization.

1808220720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7534269 (or 7534263 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 30.

The square root of 1808220720 is about 42523.1786206064. The cubic root of 1808220720 is about 1218.2894418641.

The spelling of 1808220720 in words is "one billion, eight hundred eight million, two hundred twenty thousand, seven hundred twenty".