20531219 has 2 divisors, whose sum is σ = 20531220. Its totient is φ = 20531218.

The previous prime is 20531213. The next prime is 20531243. The reversal of 20531219 is 91213502.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20531219 is a prime.

It is a super-2 number, since 2×20531219² = 843061907251922, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20531194 and 20531203.

It is not a weakly prime, because it can be changed into another prime (20531213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10265609 + 10265610.

It is an arithmetic number, because the mean of its divisors is an integer number (10265610).

Almost surely, 2^20531219 is an apocalyptic number.

20531219 is a deficient number, since it is larger than the sum of its proper divisors (1).

20531219 is an equidigital number, since it uses as much as digits as its factorization.

20531219 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 20531219 is about 4531.1388193257. The cubic root of 20531219 is about 273.8240429947.

The spelling of 20531219 in words is "twenty million, five hundred thirty-one thousand, two hundred nineteen".