1491494401 has 2 divisors, whose sum is σ = 1491494402. Its totient is φ = 1491494400.

The previous prime is 1491494399. The next prime is 1491494419. The reversal of 1491494401 is 1044941941.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1442480400 + 49014001 = 37980^2 + 7001^2 .

It is a cyclic number.

It is not a de Polignac number, because 1491494401 - 2¹ = 1491494399 is a prime.

Together with 1491494399, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1491494491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 745747200 + 745747201.

It is an arithmetic number, because the mean of its divisors is an integer number (745747201).

Almost surely, 2^1491494401 is an apocalyptic number.

It is an amenable number.

1491494401 is a deficient number, since it is larger than the sum of its proper divisors (1).

1491494401 is an equidigital number, since it uses as much as digits as its factorization.

1491494401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 1491494401 is about 38619.8705461321. The cubic root of 1491494401 is about 1142.5464777189.

The spelling of 1491494401 in words is "one billion, four hundred ninety-one million, four hundred ninety-four thousand, four hundred one".