20551456 has 12 divisors (see below), whose sum is σ = 40460742. Its totient is φ = 10275712.

The previous prime is 20551451. The next prime is 20551469. The reversal of 20551456 is 65415502.

It can be written as a sum of positive squares in only one way, i.e., 16941456 + 3610000 = 4116^2 + 1900^2 .

It is not an unprimeable number, because it can be changed into a prime (20551451) 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 as a sum of consecutive naturals, namely, 321085 + ... + 321148.

Almost surely, 2^20551456 is an apocalyptic number.

It is an amenable number.

20551456 is a deficient number, since it is larger than the sum of its proper divisors (19909286).

20551456 is an equidigital number, since it uses as much as digits as its factorization.

20551456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642243 (or 642235 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 28.

The square root of 20551456 is about 4533.3713723894. The cubic root of 20551456 is about 273.9139801371.

Adding to 20551456 its reverse (65415502), we get a palindrome (85966958).

The spelling of 20551456 in words is "twenty million, five hundred fifty-one thousand, four hundred fifty-six".