1491207993 has 18 divisors (see below), whose sum is σ = 2367585402. Its totient is φ = 903761760.

The previous prime is 1491207983. The next prime is 1491208001. The reversal of 1491207993 is 3997021941.

1491207993 is a `hidden beast` number, since 1 + 491 + 2 + 0 + 79 + 93 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1244466729 + 246741264 = 35277^2 + 15708^2 .

It is not a de Polignac number, because 1491207993 - 2¹² = 1491203897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1491207953) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 683580 + ... + 685757.

Almost surely, 2^1491207993 is an apocalyptic number.

It is an amenable number.

1491207993 is a deficient number, since it is larger than the sum of its proper divisors (876377409).

1491207993 is a wasteful number, since it uses less digits than its factorization.

1491207993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1369365 (or 1369351 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The square root of 1491207993 is about 38616.1623287452. The cubic root of 1491207993 is about 1142.4733395742.

The spelling of 1491207993 in words is "one billion, four hundred ninety-one million, two hundred seven thousand, nine hundred ninety-three".