189398640 has 80 divisors (see below), whose sum is σ = 588819456. Its totient is φ = 50361600.

The previous prime is 189398603. The next prime is 189398653. The reversal of 189398640 is 46893981.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 189398640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 102525 + ... + 104355.

Almost surely, 2^189398640 is an apocalyptic number.

189398640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 189398640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (294409728).

189398640 is an abundant number, since it is smaller than the sum of its proper divisors (399420816).

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

189398640 is a wasteful number, since it uses less digits than its factorization.

189398640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2278 (or 2272 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 48.

The square root of 189398640 is about 13762.2178445191. The cubic root of 189398640 is about 574.2825481514.

The spelling of 189398640 in words is "one hundred eighty-nine million, three hundred ninety-eight thousand, six hundred forty".