491397408 has 96 divisors (see below), whose sum is σ = 1463857920. Its totient is φ = 160300800.

The previous prime is 491397367. The next prime is 491397409. The reversal of 491397408 is 804793194.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (491397409) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34558 + ... + 46658.

It is an arithmetic number, because the mean of its divisors is an integer number (15248520).

Almost surely, 2^491397408 is an apocalyptic number.

491397408 is a gapful number since it is divisible by the number (48) 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 491397408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (731928960).

491397408 is an abundant number, since it is smaller than the sum of its proper divisors (972460512).

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

491397408 is a wasteful number, since it uses less digits than its factorization.

491397408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12167 (or 12153 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 491397408 is about 22167.4853783644. The cubic root of 491397408 is about 789.1222468131.

The spelling of 491397408 in words is "four hundred ninety-one million, three hundred ninety-seven thousand, four hundred eight".