1491699491 has 2 divisors, whose sum is σ = 1491699492. Its totient is φ = 1491699490.

The previous prime is 1491699449. The next prime is 1491699499. The reversal of 1491699491 is 1949961941.

It is a strong prime.

It is an emirp because it is prime and its reverse (1949961941) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1491699491 - 2⁶ = 1491699427 is a prime.

It is not a weakly prime, because it can be changed into another prime (1491699499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 745849745 + 745849746.

It is an arithmetic number, because the mean of its divisors is an integer number (745849746).

Almost surely, 2^1491699491 is an apocalyptic number.

1491699491 is a deficient number, since it is larger than the sum of its proper divisors (1).

1491699491 is an equidigital number, since it uses as much as digits as its factorization.

1491699491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 629856, while the sum is 53.

The square root of 1491699491 is about 38622.5256942111. The cubic root of 1491699491 is about 1142.5988444631.

The spelling of 1491699491 in words is "one billion, four hundred ninety-one million, six hundred ninety-nine thousand, four hundred ninety-one".