1991482420 has 24 divisors (see below), whose sum is σ = 4261023144. Its totient is φ = 781562496.

The previous prime is 1991482417. The next prime is 1991482421. The reversal of 1991482420 is 242841991.

It can be written as a sum of positive squares in 4 ways, for example, as 27751824 + 1963730596 = 5268^2 + 44314^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991482421) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 938319 + ... + 940438.

It is an arithmetic number, because the mean of its divisors is an integer number (177542631).

Almost surely, 2^1991482420 is an apocalyptic number.

1991482420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1991482420 is an abundant number, since it is smaller than the sum of its proper divisors (2269540724).

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

1991482420 is a wasteful number, since it uses less digits than its factorization.

1991482420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1878819 (or 1878817 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 1991482420 is about 44626.0285035538. The cubic root of 1991482420 is about 1258.1299250859.

The spelling of 1991482420 in words is "one billion, nine hundred ninety-one million, four hundred eighty-two thousand, four hundred twenty".