98128921 has 16 divisors (see below), whose sum is σ = 110392128. Its totient is φ = 86443200.

The previous prime is 98128907. The next prime is 98128957. The reversal of 98128921 is 12982189.

It is a cyclic number.

It is not a de Polignac number, because 98128921 - 2⁵ = 98128889 is a prime.

It is not an unprimeable number, because it can be changed into a prime (98168921) by changing a digit.

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

It is an upside-down number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 187366 + ... + 187888.

It is an arithmetic number, because the mean of its divisors is an integer number (6899508).

Almost surely, 2^98128921 is an apocalyptic number.

It is an amenable number.

98128921 is a deficient number, since it is larger than the sum of its proper divisors (12263207).

98128921 is a wasteful number, since it uses less digits than its factorization.

98128921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1032.

The product of its digits is 20736, while the sum is 40.

The square root of 98128921 is about 9906.0042903282. The cubic root of 98128921 is about 461.2457113851.

The spelling of 98128921 in words is "ninety-eight million, one hundred twenty-eight thousand, nine hundred twenty-one".