20705600 has 42 divisors (see below), whose sum is σ = 50952654. Its totient is φ = 8281600.

The previous prime is 20705593. The next prime is 20705621. The reversal of 20705600 is 650702.

It can be written as a sum of positive squares in 3 ways, for example, as 2930944 + 17774656 = 1712^2 + 4216^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4871 + ... + 8070.

Almost surely, 2^20705600 is an apocalyptic number.

20705600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20705600 is an abundant number, since it is smaller than the sum of its proper divisors (30247054).

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

20705600 is a wasteful number, since it uses less digits than its factorization.

20705600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12963 (or 12948 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 20.

The square root of 20705600 is about 4550.3406465890. The cubic root of 20705600 is about 274.5970959417.

The spelling of 20705600 in words is "twenty million, seven hundred five thousand, six hundred".