20529220 has 36 divisors (see below), whose sum is σ = 43929900. Its totient is φ = 8058304.

The previous prime is 20529211. The next prime is 20529221. The reversal of 20529220 is 2292502.

It can be written as a sum of positive squares in 2 ways, for example, as 4656964 + 15872256 = 2158^2 + 3984^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20529191 and 20529200.

It is not an unprimeable number, because it can be changed into a prime (20529221) 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, 137706 + ... + 137854.

It is an arithmetic number, because the mean of its divisors is an integer number (1220275).

Almost surely, 2^20529220 is an apocalyptic number.

20529220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20529220 is an abundant number, since it is smaller than the sum of its proper divisors (23400680).

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

20529220 is a wasteful number, since it uses less digits than its factorization.

20529220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324 (or 239 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 20529220 is about 4530.9182292335. The cubic root of 20529220 is about 273.8151558454.

The spelling of 20529220 in words is "twenty million, five hundred twenty-nine thousand, two hundred twenty".