2190128728 has 16 divisors (see below), whose sum is σ = 4127130000. Its totient is φ = 1089560736.

The previous prime is 2190128671. The next prime is 2190128729. The reversal of 2190128728 is 8278210912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2190128729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 686263 + ... + 689446.

It is an arithmetic number, because the mean of its divisors is an integer number (257945625).

Almost surely, 2^2190128728 is an apocalyptic number.

It is an amenable number.

2190128728 is a deficient number, since it is larger than the sum of its proper divisors (1937001272).

2190128728 is a wasteful number, since it uses less digits than its factorization.

2190128728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1375914 (or 1375910 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 40.

The square root of 2190128728 is about 46798.8111814820. The cubic root of 2190128728 is about 1298.6433041548.

The spelling of 2190128728 in words is "two billion, one hundred ninety million, one hundred twenty-eight thousand, seven hundred twenty-eight".