20128380 has 24 divisors (see below), whose sum is σ = 56359632. Its totient is φ = 5367552.

The previous prime is 20128369. The next prime is 20128387. The reversal of 20128380 is 8382102.

It is a self number, because there is not a number n which added to its sum of digits gives 20128380.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20128387) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 167677 + ... + 167796.

It is an arithmetic number, because the mean of its divisors is an integer number (2348318).

Almost surely, 2^20128380 is an apocalyptic number.

20128380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20128380 is an abundant number, since it is smaller than the sum of its proper divisors (36231252).

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

20128380 is a wasteful number, since it uses less digits than its factorization.

20128380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335485 (or 335483 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 20128380 is about 4486.4663154871. The cubic root of 20128380 is about 272.0213182541.

The spelling of 20128380 in words is "twenty million, one hundred twenty-eight thousand, three hundred eighty".