1660391648 has 24 divisors (see below), whose sum is σ = 3285501912. Its totient is φ = 825978496.

The previous prime is 1660391641. The next prime is 1660391737. The reversal of 1660391648 is 8461930661.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1660391599 and 1660391608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1660391641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 125390 + ... + 137997.

It is an arithmetic number, because the mean of its divisors is an integer number (136895913).

Almost surely, 2^1660391648 is an apocalyptic number.

It is an amenable number.

1660391648 is a deficient number, since it is larger than the sum of its proper divisors (1625110264).

1660391648 is a wasteful number, since it uses less digits than its factorization.

1660391648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263594 (or 263586 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 44.

The square root of 1660391648 is about 40747.9036025168. The cubic root of 1660391648 is about 1184.1412587124.

The spelling of 1660391648 in words is "one billion, six hundred sixty million, three hundred ninety-one thousand, six hundred forty-eight".