1491350991 has 8 divisors (see below), whose sum is σ = 2141427120. Its totient is φ = 917754432.

The previous prime is 1491350989. The next prime is 1491350999. The reversal of 1491350991 is 1990531941.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1491350991 - 2¹ = 1491350989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1491350999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19119846 + ... + 19119923.

It is an arithmetic number, because the mean of its divisors is an integer number (267678390).

Almost surely, 2^1491350991 is an apocalyptic number.

1491350991 is a deficient number, since it is larger than the sum of its proper divisors (650076129).

1491350991 is a wasteful number, since it uses less digits than its factorization.

1491350991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38239785.

The product of its (nonzero) digits is 43740, while the sum is 42.

The square root of 1491350991 is about 38618.0138147989. The cubic root of 1491350991 is about 1142.5098572122.

The spelling of 1491350991 in words is "one billion, four hundred ninety-one million, three hundred fifty thousand, nine hundred ninety-one".