20508019 has 24 divisors (see below), whose sum is σ = 25740288. Its totient is φ = 16243920.

The previous prime is 20507999. The next prime is 20508041. The reversal of 20508019 is 91080502.

It is not a de Polignac number, because 20508019 - 2⁷ = 20507891 is a prime.

It is a super-2 number, since 2×20508019² = 841157686608722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20507984 and 20508002.

It is not an unprimeable number, because it can be changed into a prime (20500019) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34644 + ... + 35230.

It is an arithmetic number, because the mean of its divisors is an integer number (1072512).

Almost surely, 2^20508019 is an apocalyptic number.

20508019 is a deficient number, since it is larger than the sum of its proper divisors (5232269).

20508019 is a wasteful number, since it uses less digits than its factorization.

20508019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 655 (or 648 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 20508019 is about 4528.5780328929. The cubic root of 20508019 is about 273.7208649657.

The spelling of 20508019 in words is "twenty million, five hundred eight thousand, nineteen".