128202591 has 16 divisors (see below), whose sum is σ = 192908160. Its totient is φ = 75018720.

The previous prime is 128202587. The next prime is 128202617. The reversal of 128202591 is 195202821.

It is not a de Polignac number, because 128202591 - 2² = 128202587 is a prime.

It is a super-2 number, since 2×128202591² = 32871808678226562, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128203591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 66025 + ... + 67938.

It is an arithmetic number, because the mean of its divisors is an integer number (12056760).

Almost surely, 2^128202591 is an apocalyptic number.

128202591 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

128202591 is a deficient number, since it is larger than the sum of its proper divisors (64705569).

128202591 is a wasteful number, since it uses less digits than its factorization.

128202591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134006.

The product of its (nonzero) digits is 2880, while the sum is 30.

The square root of 128202591 is about 11322.6583009468. The cubic root of 128202591 is about 504.2341638324.

The spelling of 128202591 in words is "one hundred twenty-eight million, two hundred two thousand, five hundred ninety-one".