20577820 has 48 divisors (see below), whose sum is σ = 47355840. Its totient is φ = 7476224.

The previous prime is 20577773. The next prime is 20577829. The reversal of 20577820 is 2877502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20577829) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8817 + ... + 10903.

It is an arithmetic number, because the mean of its divisors is an integer number (986580).

Almost surely, 2^20577820 is an apocalyptic number.

20577820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20577820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23677920).

20577820 is an abundant number, since it is smaller than the sum of its proper divisors (26778020).

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

20577820 is a wasteful number, since it uses less digits than its factorization.

20577820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2142 (or 2140 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 31.

The square root of 20577820 is about 4536.2782101630. The cubic root of 20577820 is about 274.0310583367.

The spelling of 20577820 in words is "twenty million, five hundred seventy-seven thousand, eight hundred twenty".