20663878 has 8 divisors (see below), whose sum is σ = 31066200. Its totient is φ = 10308480.

The previous prime is 20663861. The next prime is 20663927. The reversal of 20663878 is 87836602.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×20663878³ (a number of 23 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20663878.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 10608 + ... + 12403.

It is an arithmetic number, because the mean of its divisors is an integer number (3883275).

Almost surely, 2^20663878 is an apocalyptic number.

20663878 is a deficient number, since it is larger than the sum of its proper divisors (10402322).

20663878 is a wasteful number, since it uses less digits than its factorization.

20663878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23462.

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 20663878 is about 4545.7538428736. The cubic root of 20663878 is about 274.4125332499.

The spelling of 20663878 in words is "twenty million, six hundred sixty-three thousand, eight hundred seventy-eight".