20678660 has 24 divisors (see below), whose sum is σ = 43519896. Its totient is φ = 8253440.

The previous prime is 20678659. The next prime is 20678677. The reversal of 20678660 is 6687602.

It can be written as a sum of positive squares in 4 ways, for example, as 6959044 + 13719616 = 2638^2 + 3704^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20678660.

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, 12014 + ... + 13626.

It is an arithmetic number, because the mean of its divisors is an integer number (1813329).

Almost surely, 2^20678660 is an apocalyptic number.

20678660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20678660 is an abundant number, since it is smaller than the sum of its proper divisors (22841236).

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

20678660 is a wasteful number, since it uses less digits than its factorization.

20678660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2263 (or 2261 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 20678660 is about 4547.3794651425. The cubic root of 20678660 is about 274.4779517417.

The spelling of 20678660 in words is "twenty million, six hundred seventy-eight thousand, six hundred sixty".