20678538 has 16 divisors (see below), whose sum is σ = 41767776. Its totient is φ = 6824400.

The previous prime is 20678531. The next prime is 20678549. The reversal of 20678538 is 83587602.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20678496 and 20678505.

It is not an unprimeable number, because it can be changed into a prime (20678531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16456 + ... + 17667.

It is an arithmetic number, because the mean of its divisors is an integer number (2610486).

Almost surely, 2^20678538 is an apocalyptic number.

20678538 is an abundant number, since it is smaller than the sum of its proper divisors (21089238).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20678538 is a wasteful number, since it uses less digits than its factorization.

20678538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34229.

The product of its (nonzero) digits is 80640, while the sum is 39.

The square root of 20678538 is about 4547.3660508035. The cubic root of 20678538 is about 274.4774119522.

The spelling of 20678538 in words is "twenty million, six hundred seventy-eight thousand, five hundred thirty-eight".