20500380 has 36 divisors (see below), whose sum is σ = 62185032. Its totient is φ = 5466720.

The previous prime is 20500367. The next prime is 20500387. The reversal of 20500380 is 8300502.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20500387) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 56766 + ... + 57125.

It is an arithmetic number, because the mean of its divisors is an integer number (1727362).

Almost surely, 2^20500380 is an apocalyptic number.

20500380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20500380 is an abundant number, since it is smaller than the sum of its proper divisors (41684652).

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

20500380 is a wasteful number, since it uses less digits than its factorization.

20500380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113906 (or 113901 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 20500380 is about 4527.7345328542. The cubic root of 20500380 is about 273.6868747924.

Adding to 20500380 its reverse (8300502), we get a palindrome (28800882).

The spelling of 20500380 in words is "twenty million, five hundred thousand, three hundred eighty".