491657040 has 240 divisors, whose sum is σ = 1957458048. Its totient is φ = 112347648.

The previous prime is 491657029. The next prime is 491657041. The reversal of 491657040 is 40756194.

491657040 is a `hidden beast` number, since 49 + 1 + 6 + 570 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

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 = 491656986 and 491657004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491657041) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 134274 + ... + 137886.

Almost surely, 2^491657040 is an apocalyptic number.

491657040 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 491657040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (978729024).

491657040 is an abundant number, since it is smaller than the sum of its proper divisors (1465801008).

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

491657040 is a wasteful number, since it uses less digits than its factorization.

491657040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3648 (or 3630 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 491657040 is about 22173.3407496480. The cubic root of 491657040 is about 789.2612010900.

The spelling of 491657040 in words is "four hundred ninety-one million, six hundred fifty-seven thousand, forty".