20570820 has 24 divisors (see below), whose sum is σ = 57598464. Its totient is φ = 5485536.

The previous prime is 20570789. The next prime is 20570821. The reversal of 20570820 is 2807502.

It is not an unprimeable number, because it can be changed into a prime (20570821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 171364 + ... + 171483.

It is an arithmetic number, because the mean of its divisors is an integer number (2399936).

Almost surely, 2^20570820 is an apocalyptic number.

20570820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20570820 is an abundant number, since it is smaller than the sum of its proper divisors (37027644).

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

20570820 is a wasteful number, since it uses less digits than its factorization.

20570820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 342859 (or 342857 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 24.

The square root of 20570820 is about 4535.5065869206. The cubic root of 20570820 is about 273.9999822402. Note that the first 4 decimals are identical.

The spelling of 20570820 in words is "twenty million, five hundred seventy thousand, eight hundred twenty".