20656144 has 10 divisors (see below), whose sum is σ = 40021310. Its totient is φ = 10328064.

The previous prime is 20656121. The next prime is 20656183. The reversal of 20656144 is 44165602.

It can be written as a sum of positive squares in only one way, i.e., 18662400 + 1993744 = 4320^2 + 1412^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645489 + ... + 645520.

It is an arithmetic number, because the mean of its divisors is an integer number (4002131).

Almost surely, 2^20656144 is an apocalyptic number.

It is an amenable number.

20656144 is a deficient number, since it is larger than the sum of its proper divisors (19365166).

20656144 is a wasteful number, since it uses less digits than its factorization.

20656144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1291017 (or 1291011 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 20656144 is about 4544.9030792746. The cubic root of 20656144 is about 274.3782936078.

The spelling of 20656144 in words is "twenty million, six hundred fifty-six thousand, one hundred forty-four".