20656478 has 16 divisors (see below), whose sum is σ = 32156160. Its totient is φ = 9941400.

The previous prime is 20656463. The next prime is 20656483. The reversal of 20656478 is 87465602.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12293 + ... + 13871.

It is an arithmetic number, because the mean of its divisors is an integer number (2009760).

Almost surely, 2^20656478 is an apocalyptic number.

20656478 is a deficient number, since it is larger than the sum of its proper divisors (11499682).

20656478 is a wasteful number, since it uses less digits than its factorization.

20656478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1823.

The product of its (nonzero) digits is 80640, while the sum is 38.

The square root of 20656478 is about 4544.9398235840. The cubic root of 20656478 is about 274.3797724552.

The spelling of 20656478 in words is "twenty million, six hundred fifty-six thousand, four hundred seventy-eight".