20781201 has 8 divisors (see below), whose sum is σ = 31666624. Its totient is φ = 11874960.

The previous prime is 20781199. The next prime is 20781217. The reversal of 20781201 is 10218702.

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

It is not a de Polignac number, because 20781201 - 2¹ = 20781199 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 989581 = 20781201 / (2 + 0 + 7 + 8 + 1 + 2 + 0 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20781221) 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 7 ways as a sum of consecutive naturals, for example, 494770 + ... + 494811.

It is an arithmetic number, because the mean of its divisors is an integer number (3958328).

Almost surely, 2^20781201 is an apocalyptic number.

20781201 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20781201 is a deficient number, since it is larger than the sum of its proper divisors (10885423).

20781201 is an equidigital number, since it uses as much as digits as its factorization.

20781201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 989591.

The product of its (nonzero) digits is 224, while the sum is 21.

The square root of 20781201 is about 4558.6402577962. The cubic root of 20781201 is about 274.9308961352.

Adding to 20781201 its reverse (10218702), we get a palindrome (30999903).

The spelling of 20781201 in words is "twenty million, seven hundred eighty-one thousand, two hundred one".