20766720 has 168 divisors, whose sum is σ = 71954136. Its totient is φ = 5111808.

The previous prime is 20766701. The next prime is 20766751. The reversal of 20766720 is 2766702.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1597434 + ... + 1597446.

Almost surely, 2^20766720 is an apocalyptic number.

20766720 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 20766720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35977068).

20766720 is an abundant number, since it is smaller than the sum of its proper divisors (51187416).

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

20766720 is an equidigital number, since it uses as much as digits as its factorization.

20766720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60 (or 23 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 30.

The square root of 20766720 is about 4557.0516784430. The cubic root of 20766720 is about 274.8670211066.

Multiplying 20766720 by its sum of digits (30), we get a square (623001600 = 24960²).

20766720 divided by its sum of digits (30) gives a square (692224 = 832²).

The spelling of 20766720 in words is "twenty million, seven hundred sixty-six thousand, seven hundred twenty".