2121260728 has 8 divisors (see below), whose sum is σ = 3977363880. Its totient is φ = 1060630360.

The previous prime is 2121260723. The next prime is 2121260741. The reversal of 2121260728 is 8270621212.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 2121260728.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121260723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132578788 + ... + 132578803.

It is an arithmetic number, because the mean of its divisors is an integer number (497170485).

Almost surely, 2^2121260728 is an apocalyptic number.

It is an amenable number.

2121260728 is a deficient number, since it is larger than the sum of its proper divisors (1856103152).

2121260728 is a wasteful number, since it uses less digits than its factorization.

2121260728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265157597 (or 265157593 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 31.

The square root of 2121260728 is about 46057.1463293157. The cubic root of 2121260728 is about 1284.8862567947.

The spelling of 2121260728 in words is "two billion, one hundred twenty-one million, two hundred sixty thousand, seven hundred twenty-eight".