1491999938 has 54 divisors (see below), whose sum is σ = 2677752441. Its totient is φ = 622736400.

The previous prime is 1491999931. The next prime is 1491999941. The reversal of 1491999938 is 8399991941.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1275704089 + 216295849 = 35717^2 + 14707^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=27313.

Its product of digits (5668704) is a multiple of the sum of its prime factors (432).

It is not an unprimeable number, because it can be changed into a prime (1491999931) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 7811423 + ... + 7811613.

Almost surely, 2^1491999938 is an apocalyptic number.

1491999938 is a deficient number, since it is larger than the sum of its proper divisors (1185752503).

1491999938 is a wasteful number, since it uses less digits than its factorization.

1491999938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432 (or 217 counting only the distinct ones).

The product of its digits is 5668704, while the sum is 62.

The square root of 1491999938 is about 38626.4150290963. The cubic root of 1491999938 is about 1142.6755505629.

The spelling of 1491999938 in words is "one billion, four hundred ninety-one million, nine hundred ninety-nine thousand, nine hundred thirty-eight".