491451840 has 224 divisors, whose sum is σ = 1891710720. Its totient is φ = 119116800.

The previous prime is 491451823. The next prime is 491451869. The reversal of 491451840 is 48154194.

It is a super-2 number, since 2×491451840² = 483049822078771200, which contains 22 as substring.

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 = 491451795 and 491451804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 92455 + ... + 97625.

Almost surely, 2^491451840 is an apocalyptic number.

491451840 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 491451840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (945855360).

491451840 is an abundant number, since it is smaller than the sum of its proper divisors (1400258880).

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

491451840 is a wasteful number, since it uses less digits than its factorization.

491451840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5208 (or 5192 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 491451840 is about 22168.7130884948. The cubic root of 491451840 is about 789.1513827125.

The spelling of 491451840 in words is "four hundred ninety-one million, four hundred fifty-one thousand, eight hundred forty".