20481566 has 32 divisors (see below), whose sum is σ = 37988352. Its totient is φ = 8081280.

The previous prime is 20481557. The next prime is 20481577. The reversal of 20481566 is 66518402.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 10271 + ... + 12101.

It is an arithmetic number, because the mean of its divisors is an integer number (1187136).

Almost surely, 2^20481566 is an apocalyptic number.

20481566 is a deficient number, since it is larger than the sum of its proper divisors (17506786).

20481566 is a wasteful number, since it uses less digits than its factorization.

20481566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1904.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 20481566 is about 4525.6564164771. The cubic root of 20481566 is about 273.6031247862.

Adding to 20481566 its reverse (66518402), we get a palindrome (86999968).

The spelling of 20481566 in words is "twenty million, four hundred eighty-one thousand, five hundred sixty-six".