189658640 has 20 divisors (see below), whose sum is σ = 440956524. Its totient is φ = 75863424.

The previous prime is 189658631. The next prime is 189658643. The reversal of 189658640 is 46856981.

189658640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 95335696 + 94322944 = 9764^2 + 9712^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (189658643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1185287 + ... + 1185446.

Almost surely, 2^189658640 is an apocalyptic number.

189658640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

189658640 is an abundant number, since it is smaller than the sum of its proper divisors (251297884).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

189658640 is a wasteful number, since it uses less digits than its factorization.

189658640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2370746 (or 2370740 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 47.

The square root of 189658640 is about 13771.6607567860. The cubic root of 189658640 is about 574.5452131675.

The spelling of 189658640 in words is "one hundred eighty-nine million, six hundred fifty-eight thousand, six hundred forty".