20121020 has 24 divisors (see below), whose sum is σ = 42357168. Its totient is φ = 8028800.

The previous prime is 20120999. The next prime is 20121043. The reversal of 20121020 is 2012102.

It is a junction number, because it is equal to n+sod(n) for n = 20120989 and 20121007.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9455 + ... + 11385.

It is an arithmetic number, because the mean of its divisors is an integer number (1764882).

Almost surely, 2^20121020 is an apocalyptic number.

20121020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121020 is an abundant number, since it is smaller than the sum of its proper divisors (22236148).

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

20121020 is a wasteful number, since it uses less digits than its factorization.

20121020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2461 (or 2459 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 8.

The square root of 20121020 is about 4485.6459958405. The cubic root of 20121020 is about 271.9881590866.

Adding to 20121020 its reverse (2012102), we get a palindrome (22133122).

The spelling of 20121020 in words is "twenty million, one hundred twenty-one thousand, twenty".