20878983 has 6 divisors (see below), whose sum is σ = 30158544.
Its totient is φ = 13919316.
The previous prime is 20878981. The next prime is 20878987. The reversal of 20878983 is 38987802.
It is not a de Polignac number, because 20878983 - 21 = 20878981 is a prime.
It is a super-2 number, since 2×208789832 = 871863862228578, which contains 22 as substring.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (20878981) by changing a digit.
It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1159935 + ... + 1159952.
It is an arithmetic number, because the mean of its divisors is an integer number (5026424).
Almost surely, 220878983 is an apocalyptic number.
20878983 is a deficient number, since it is larger than the sum of its proper divisors (9279561).
20878983 is a wasteful number, since it uses less digits than its factorization.
20878983 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 2319893 (or 2319890 counting only the distinct ones).
The product of its (nonzero) digits is 193536, while the sum is 45.
The square root of 20878983 is about 4569.3525799614.
The cubic root of 20878983 is about 275.3614332990.
The spelling of 20878983 in words is "twenty million, eight hundred seventy-eight thousand, nine hundred eighty-three".