20766240 has 384 divisors, whose sum is σ = 87091200. Its totient is φ = 4561920.

The previous prime is 20766211. The next prime is 20766241. The reversal of 20766240 is 4266702.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20766241) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 902869 + ... + 902891.

It is an arithmetic number, because the mean of its divisors is an integer number (226800).

Almost surely, 2^20766240 is an apocalyptic number.

20766240 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 20766240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43545600).

20766240 is an abundant number, since it is smaller than the sum of its proper divisors (66324960).

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

20766240 is a wasteful number, since it uses less digits than its factorization.

20766240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77 (or 63 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 20766240 is about 4556.9990125081. Note that the first 3 decimals coincide. The cubic root of 20766240 is about 274.8649033402.

It can be divided in two parts, 207662 and 40, that added together give a palindrome (207702).

The spelling of 20766240 in words is "twenty million, seven hundred sixty-six thousand, two hundred forty".