1491494399 has 2 divisors, whose sum is σ = 1491494400. Its totient is φ = 1491494398.

The previous prime is 1491494387. The next prime is 1491494401. The reversal of 1491494399 is 9934941941.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1491494399 - 2²⁸ = 1223058943 is a prime.

Together with 1491494401, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1491494399.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1491094399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 745747199 + 745747200.

It is an arithmetic number, because the mean of its divisors is an integer number (745747200).

Almost surely, 2^1491494399 is an apocalyptic number.

1491494399 is a deficient number, since it is larger than the sum of its proper divisors (1).

1491494399 is an equidigital number, since it uses as much as digits as its factorization.

1491494399 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1259712, while the sum is 53.

The square root of 1491494399 is about 38619.8705202387. The cubic root of 1491494399 is about 1142.5464772082.

The spelling of 1491494399 in words is "one billion, four hundred ninety-one million, four hundred ninety-four thousand, three hundred ninety-nine".