20822581 has 8 divisors (see below), whose sum is σ = 22597344. Its totient is φ = 19072560.

The previous prime is 20822579. The next prime is 20822591. The reversal of 20822581 is 18522802.

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

It is not a de Polignac number, because 20822581 - 2¹ = 20822579 is a prime.

It is a super-2 number, since 2×20822581² = 867159759003122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20822531) 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, 4411 + ... + 7816.

It is an arithmetic number, because the mean of its divisors is an integer number (2824668).

Almost surely, 2^20822581 is an apocalyptic number.

It is an amenable number.

20822581 is a deficient number, since it is larger than the sum of its proper divisors (1774763).

20822581 is a wasteful number, since it uses less digits than its factorization.

20822581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12371.

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 20822581 is about 4563.1766347579. The cubic root of 20822581 is about 275.1132580318.

The spelling of 20822581 in words is "twenty million, eight hundred twenty-two thousand, five hundred eighty-one".