20678820 has 48 divisors (see below), whose sum is σ = 58459968. Its totient is φ = 5461120.

The previous prime is 20678809. The next prime is 20678831. The reversal of 20678820 is 2887602.

It is an interprime number because it is at equal distance from previous prime (20678809) and next prime (20678831).

It is a super-2 number, since 2×20678820² = 855227193184800, which contains 22 as substring.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 4810 + ... + 8030.

It is an arithmetic number, because the mean of its divisors is an integer number (1217916).

Almost surely, 2^20678820 is an apocalyptic number.

20678820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20678820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29229984).

20678820 is an abundant number, since it is smaller than the sum of its proper divisors (37781148).

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

20678820 is a wasteful number, since it uses less digits than its factorization.

20678820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3340 (or 3338 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 20678820 is about 4547.3970576584. The cubic root of 20678820 is about 274.4786596593.

The spelling of 20678820 in words is "twenty million, six hundred seventy-eight thousand, eight hundred twenty".