491713664400 has 1920 divisors, whose sum is σ = 2231857152000. Its totient is φ = 100236165120.

The previous prime is 491713664357. The next prime is 491713664443. The reversal of 491713664400 is 4466317194.

491713664400 is a `hidden beast` number, since 4 + 9 + 171 + 36 + 6 + 440 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (491713664357) and next prime (491713664443).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 2944393117 + ... + 2944393283.

It is an arithmetic number, because the mean of its divisors is an integer number (1162425600).

Almost surely, 2^491713664400 is an apocalyptic number.

491713664400 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 491713664400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1115928576000).

491713664400 is an abundant number, since it is smaller than the sum of its proper divisors (1740143487600).

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

491713664400 is a wasteful number, since it uses less digits than its factorization.

491713664400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326 (or 309 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The spelling of 491713664400 in words is "four hundred ninety-one billion, seven hundred thirteen million, six hundred sixty-four thousand, four hundred".