20705660 has 24 divisors (see below), whose sum is σ = 46040400. Its totient is φ = 7794944.

The previous prime is 20705653. The next prime is 20705683. The reversal of 20705660 is 6650702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30110 + ... + 30789.

It is an arithmetic number, because the mean of its divisors is an integer number (1918350).

Almost surely, 2^20705660 is an apocalyptic number.

20705660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20705660 is an abundant number, since it is smaller than the sum of its proper divisors (25334740).

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

20705660 is a wasteful number, since it uses less digits than its factorization.

20705660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60925 (or 60923 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 26.

The square root of 20705660 is about 4550.3472394972. The cubic root of 20705660 is about 274.5973611809.

The spelling of 20705660 in words is "twenty million, seven hundred five thousand, six hundred sixty".