491442840 has 384 divisors, whose sum is σ = 1949875200. Its totient is φ = 104924160.

The previous prime is 491442821. The next prime is 491442841. The reversal of 491442840 is 48244194.

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

It is a junction number, because it is equal to n+sod(n) for n = 491442795 and 491442804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491442841) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3535491 + ... + 3535629.

It is an arithmetic number, because the mean of its divisors is an integer number (5077800).

Almost surely, 2^491442840 is an apocalyptic number.

491442840 is a gapful number since it is divisible by the number (40) 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 491442840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (974937600).

491442840 is an abundant number, since it is smaller than the sum of its proper divisors (1458432360).

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

491442840 is a wasteful number, since it uses less digits than its factorization.

491442840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 491442840 is about 22168.5100987865. The cubic root of 491442840 is about 789.1465654172.

It can be divided in two parts, 49144 and 2840, that added together give a square (51984 = 228²).

The spelling of 491442840 in words is "four hundred ninety-one million, four hundred forty-two thousand, eight hundred forty".