20605700 has 108 divisors (see below), whose sum is σ = 51163392. Its totient is φ = 7180800.

The previous prime is 20605699. The next prime is 20605703. The reversal of 20605700 is 750602.

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

It is not an unprimeable number, because it can be changed into a prime (20605703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 664685 + ... + 664715.

Almost surely, 2^20605700 is an apocalyptic number.

20605700 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 20605700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25581696).

20605700 is an abundant number, since it is smaller than the sum of its proper divisors (30557692).

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

20605700 is a wasteful number, since it uses less digits than its factorization.

20605700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102 (or 78 counting only the distinct ones).

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

The square root of 20605700 is about 4539.3501737584. The cubic root of 20605700 is about 274.1547601045.

The spelling of 20605700 in words is "twenty million, six hundred five thousand, seven hundred".