20667280 has 40 divisors (see below), whose sum is σ = 49231224. Its totient is φ = 8064000.

The previous prime is 20667277. The next prime is 20667281. The reversal of 20667280 is 8276602.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 200704 + 20466576 = 448^2 + 4524^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (20667281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 130 + ... + 6430.

Almost surely, 2^20667280 is an apocalyptic number.

20667280 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 20667280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24615612).

20667280 is an abundant number, since it is smaller than the sum of its proper divisors (28563944).

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

20667280 is a wasteful number, since it uses less digits than its factorization.

20667280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6355 (or 6349 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 20667280 is about 4546.1280228344. The cubic root of 20667280 is about 274.4275917368.

The spelling of 20667280 in words is "twenty million, six hundred sixty-seven thousand, two hundred eighty".