1660405376 has 128 divisors (see below), whose sum is σ = 3929040000. Its totient is φ = 698449920.

The previous prime is 1660405343. The next prime is 1660405381. The reversal of 1660405376 is 6735040661.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2590016 + ... + 2590656.

It is an arithmetic number, because the mean of its divisors is an integer number (30695625).

Almost surely, 2^1660405376 is an apocalyptic number.

1660405376 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1660405376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1964520000).

1660405376 is an abundant number, since it is smaller than the sum of its proper divisors (2268634624).

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

1660405376 is an frugal number, since it uses more digits than its factorization.

1660405376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 735 (or 709 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 38.

The square root of 1660405376 is about 40748.0720525524. The cubic root of 1660405376 is about 1184.1445221686.

The spelling of 1660405376 in words is "one billion, six hundred sixty million, four hundred five thousand, three hundred seventy-six".