128211994 has 8 divisors (see below), whose sum is σ = 203630868. Its totient is φ = 60335040.

The previous prime is 128211991. The next prime is 128212033. The reversal of 128211994 is 499112821.

It can be written as a sum of positive squares in 2 ways, for example, as 125731369 + 2480625 = 11213^2 + 1575^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (128211991) 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, 1885437 + ... + 1885504.

Almost surely, 2^128211994 is an apocalyptic number.

128211994 is a deficient number, since it is larger than the sum of its proper divisors (75418874).

128211994 is a wasteful number, since it uses less digits than its factorization.

128211994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3770960.

The product of its digits is 10368, while the sum is 37.

The square root of 128211994 is about 11323.0735226793. The cubic root of 128211994 is about 504.2464911909.

The spelling of 128211994 in words is "one hundred twenty-eight million, two hundred eleven thousand, nine hundred ninety-four".