189788421 has 16 divisors (see below), whose sum is σ = 258185664. Its totient is φ = 123978624.

The previous prime is 189788411. The next prime is 189788453. The reversal of 189788421 is 124887981.

It is a de Polignac number, because none of the positive numbers 2^k-189788421 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189788411) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37201 + ... + 41993.

It is an arithmetic number, because the mean of its divisors is an integer number (16136604).

Almost surely, 2^189788421 is an apocalyptic number.

It is an amenable number.

189788421 is a deficient number, since it is larger than the sum of its proper divisors (68397243).

189788421 is a wasteful number, since it uses less digits than its factorization.

189788421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5060.

The product of its digits is 258048, while the sum is 48.

The square root of 189788421 is about 13776.3718373162. The cubic root of 189788421 is about 574.6762346188.

The spelling of 189788421 in words is "one hundred eighty-nine million, seven hundred eighty-eight thousand, four hundred twenty-one".