1491987804 has 12 divisors (see below), whose sum is σ = 3481304904. Its totient is φ = 497329264.

The previous prime is 1491987793. The next prime is 1491987817. The reversal of 1491987804 is 4087891941.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62166147 + ... + 62166170.

It is an arithmetic number, because the mean of its divisors is an integer number (290108742).

Almost surely, 2^1491987804 is an apocalyptic number.

It is an amenable number.

1491987804 is an abundant number, since it is smaller than the sum of its proper divisors (1989317100).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1491987804 is a wasteful number, since it uses less digits than its factorization.

1491987804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124332324 (or 124332322 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 51.

The square root of 1491987804 is about 38626.2579600976. The cubic root of 1491987804 is about 1142.6724528723.

The spelling of 1491987804 in words is "one billion, four hundred ninety-one million, nine hundred eighty-seven thousand, eight hundred four".