1491657216 has 120 divisors (see below), whose sum is σ = 4622896080. Its totient is φ = 426166272.

The previous prime is 1491657161. The next prime is 1491657241. The reversal of 1491657216 is 6127561941.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65355 + ... + 85173.

It is an arithmetic number, because the mean of its divisors is an integer number (38524134).

Almost surely, 2^1491657216 is an apocalyptic number.

1491657216 is a gapful number since it is divisible by the number (16) 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 1491657216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2311448040).

1491657216 is an abundant number, since it is smaller than the sum of its proper divisors (3131238864).

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

1491657216 is an equidigital number, since it uses as much as digits as its factorization.

1491657216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19854 (or 19831 counting only the distinct ones).

The product of its digits is 90720, while the sum is 42.

The square root of 1491657216 is about 38621.9784060838. The cubic root of 1491657216 is about 1142.5880505504.

The spelling of 1491657216 in words is "one billion, four hundred ninety-one million, six hundred fifty-seven thousand, two hundred sixteen".