20185380 has 72 divisors (see below), whose sum is σ = 61780992. Its totient is φ = 5334336.

The previous prime is 20185379. The next prime is 20185381. The reversal of 20185380 is 8358102.

It is a happy number.

20185380 is a `hidden beast` number, since 201 + 85 + 380 = 666.

It is an interprime number because it is at equal distance from previous prime (20185379) and next prime (20185381).

It is not an unprimeable number, because it can be changed into a prime (20185381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22419 + ... + 23301.

Almost surely, 2^20185380 is an apocalyptic number.

20185380 is a gapful number since it is divisible by the number (20) 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 20185380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30890496).

20185380 is an abundant number, since it is smaller than the sum of its proper divisors (41595612).

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

20185380 is a wasteful number, since it uses less digits than its factorization.

20185380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1025 (or 1020 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 20185380 is about 4492.8142627979. The cubic root of 20185380 is about 272.2778482898.

The spelling of 20185380 in words is "twenty million, one hundred eighty-five thousand, three hundred eighty".