2128263656 has 8 divisors (see below), whose sum is σ = 3990494370. Its totient is φ = 1064131824.

The previous prime is 2128263653. The next prime is 2128263661. The reversal of 2128263656 is 6563628212.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1501562500 + 626701156 = 38750^2 + 25034^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (2128263653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133016471 + ... + 133016486.

Almost surely, 2^2128263656 is an apocalyptic number.

It is an amenable number.

2128263656 is a deficient number, since it is larger than the sum of its proper divisors (1862230714).

2128263656 is a wasteful number, since it uses less digits than its factorization.

2128263656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266032963 (or 266032959 counting only the distinct ones).

The product of its digits is 207360, while the sum is 41.

The square root of 2128263656 is about 46133.1080244980. The cubic root of 2128263656 is about 1286.2986373774.

The spelling of 2128263656 in words is "two billion, one hundred twenty-eight million, two hundred sixty-three thousand, six hundred fifty-six".