1605996672 has 128 divisors (see below), whose sum is σ = 4967775360. Its totient is φ = 450158592.

The previous prime is 1605996671. The next prime is 1605996683. The reversal of 1605996672 is 2766995061.

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

It is not an unprimeable number, because it can be changed into a prime (1605996671) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 136828 + ... + 148100.

It is an arithmetic number, because the mean of its divisors is an integer number (38810745).

Almost surely, 2^1605996672 is an apocalyptic number.

1605996672 is a gapful number since it is divisible by the number (12) 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 1605996672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2483887680).

1605996672 is an abundant number, since it is smaller than the sum of its proper divisors (3361778688).

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

1605996672 is a wasteful number, since it uses less digits than its factorization.

1605996672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11350 (or 11338 counting only the distinct ones).

The product of its (nonzero) digits is 1224720, while the sum is 51.

The square root of 1605996672 is about 40074.8882967876. Note that the first 3 decimals coincide. The cubic root of 1605996672 is about 1171.0664715338.

The spelling of 1605996672 in words is "one billion, six hundred five million, nine hundred ninety-six thousand, six hundred seventy-two".