1491558660 has 36 divisors (see below), whose sum is σ = 4524395148. Its totient is φ = 397748928.

The previous prime is 1491558659. The next prime is 1491558697. The reversal of 1491558660 is 668551941.

1491558660 is a `hidden beast` number, since 1 + 4 + 9 + 1 + 5 + 586 + 60 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 822198276 + 669360384 = 28674^2 + 25872^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4143039 + ... + 4143398.

It is an arithmetic number, because the mean of its divisors is an integer number (125677643).

Almost surely, 2^1491558660 is an apocalyptic number.

1491558660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1491558660 is an abundant number, since it is smaller than the sum of its proper divisors (3032836488).

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

1491558660 is a wasteful number, since it uses less digits than its factorization.

1491558660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8286452 (or 8286447 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 45.

The square root of 1491558660 is about 38620.7024793698. The cubic root of 1491558660 is about 1142.5628858350.

The spelling of 1491558660 in words is "one billion, four hundred ninety-one million, five hundred fifty-eight thousand, six hundred sixty".