189640720 has 40 divisors (see below), whose sum is σ = 443650176. Its totient is φ = 75385728.

The previous prime is 189640699. The next prime is 189640741. The reversal of 189640720 is 27046981.

It is an interprime number because it is at equal distance from previous prime (189640699) and next prime (189640741).

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 189640720.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5769 + ... + 20311.

Almost surely, 2^189640720 is an apocalyptic number.

189640720 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 189640720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (221825088).

189640720 is an abundant number, since it is smaller than the sum of its proper divisors (254009456).

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

189640720 is a wasteful number, since it uses less digits than its factorization.

189640720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14719 (or 14713 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 189640720 is about 13771.0101299796. The cubic root of 189640720 is about 574.5271171916.

The spelling of 189640720 in words is "one hundred eighty-nine million, six hundred forty thousand, seven hundred twenty".