20380521 has 24 divisors (see below), whose sum is σ = 33278880. Its totient is φ = 11031552.

The previous prime is 20380489. The next prime is 20380537. The reversal of 20380521 is 12508302.

It is not a de Polignac number, because 20380521 - 2⁵ = 20380489 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (20380541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 856 + ... + 6441.

It is an arithmetic number, because the mean of its divisors is an integer number (1386620).

Almost surely, 2^20380521 is an apocalyptic number.

20380521 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20380521 is a deficient number, since it is larger than the sum of its proper divisors (12898359).

20380521 is a wasteful number, since it uses less digits than its factorization.

20380521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7333 (or 7326 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 20380521 is about 4514.4790397121. The cubic root of 20380521 is about 273.1524460861.

Adding to 20380521 its reverse (12508302), we get a palindrome (32888823).

The spelling of 20380521 in words is "twenty million, three hundred eighty thousand, five hundred twenty-one".