21280801 has 8 divisors (see below), whose sum is σ = 21953664. Its totient is φ = 20617200.

The previous prime is 21280793. The next prime is 21280807. The reversal of 21280801 is 10808212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21280801 - 2³ = 21280793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21280807) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2506 + ... + 6988.

It is an arithmetic number, because the mean of its divisors is an integer number (2744208).

Almost surely, 2^21280801 is an apocalyptic number.

It is an amenable number.

21280801 is a deficient number, since it is larger than the sum of its proper divisors (672863).

21280801 is a wasteful number, since it uses less digits than its factorization.

21280801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4631.

The product of its (nonzero) digits is 256, while the sum is 22.

The square root of 21280801 is about 4613.1118564370. Note that the first 3 decimals coincide. The cubic root of 21280801 is about 277.1166733407.

The spelling of 21280801 in words is "twenty-one million, two hundred eighty thousand, eight hundred one".