5181611920 has 20 divisors (see below), whose sum is σ = 12047247900. Its totient is φ = 2072644736.

The previous prime is 5181611909. The next prime is 5181611921. The reversal of 5181611920 is 291161815.

It can be written as a sum of positive squares in 2 ways, for example, as 1541661696 + 3639950224 = 39264^2 + 60332^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (5181611921) 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, 32384995 + ... + 32385154.

It is an arithmetic number, because the mean of its divisors is an integer number (602362395).

Almost surely, 2^5181611920 is an apocalyptic number.

It is an amenable number.

5181611920 is an abundant number, since it is smaller than the sum of its proper divisors (6865635980).

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

5181611920 is a wasteful number, since it uses less digits than its factorization.

5181611920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64770162 (or 64770156 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 34.

The square root of 5181611920 is about 71983.4142007727. The cubic root of 5181611920 is about 1730.4336868100.

It can be divided in two parts, 51816 and 11920, that added together give a palindrome (63736).

The spelling of 5181611920 in words is "five billion, one hundred eighty-one million, six hundred eleven thousand, nine hundred twenty".