20510220 has 48 divisors (see below), whose sum is σ = 59286528. Its totient is φ = 5292480.

The previous prime is 20510219. The next prime is 20510233. The reversal of 20510220 is 2201502.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 20510196 and 20510205.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3654 + ... + 7373.

It is an arithmetic number, because the mean of its divisors is an integer number (1235136).

Almost surely, 2^20510220 is an apocalyptic number.

20510220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20510220 is an abundant number, since it is smaller than the sum of its proper divisors (38776308).

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

20510220 is a wasteful number, since it uses less digits than its factorization.

20510220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11070 (or 11068 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 12.

The square root of 20510220 is about 4528.8210386369. The cubic root of 20510220 is about 273.7306568764.

Adding to 20510220 its reverse (2201502), we get a palindrome (22711722).

The spelling of 20510220 in words is "twenty million, five hundred ten thousand, two hundred twenty".