20671801 has 4 divisors (see below), whose sum is σ = 20776932. Its totient is φ = 20566672.

The previous prime is 20671769. The next prime is 20671811. The reversal of 20671801 is 10817602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10817602 = 2 ⋅5408801.

It can be written as a sum of positive squares in 2 ways, for example, as 16362025 + 4309776 = 4045^2 + 2076^2 .

It is a cyclic number.

It is not a de Polignac number, because 20671801 - 2⁵ = 20671769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20671811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52270 + ... + 52663.

It is an arithmetic number, because the mean of its divisors is an integer number (5194233).

Almost surely, 2^20671801 is an apocalyptic number.

It is an amenable number.

20671801 is a deficient number, since it is larger than the sum of its proper divisors (105131).

20671801 is a wasteful number, since it uses less digits than its factorization.

20671801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105130.

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 20671801 is about 4546.6252319715. The cubic root of 20671801 is about 274.4476007670.

The spelling of 20671801 in words is "twenty million, six hundred seventy-one thousand, eight hundred one".