1840491720 has 144 divisors (see below), whose sum is σ = 6212229660. Its totient is φ = 490727808.

The previous prime is 1840491713. The next prime is 1840491739. The reversal of 1840491720 is 271940481.

It can be written as a sum of positive squares in 2 ways, for example, as 1815271236 + 25220484 = 42606^2 + 5022^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 258934 + ... + 265946.

Almost surely, 2^1840491720 is an apocalyptic number.

1840491720 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 1840491720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3106114830).

1840491720 is an abundant number, since it is smaller than the sum of its proper divisors (4371737940).

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

1840491720 is an frugal number, since it uses more digits than its factorization.

1840491720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7048 (or 7023 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 1840491720 is about 42900.9524369798. The cubic root of 1840491720 is about 1225.4942822761.

The spelling of 1840491720 in words is "one billion, eight hundred forty million, four hundred ninety-one thousand, seven hundred twenty".