20309219 has 4 divisors (see below), whose sum is σ = 23210544. Its totient is φ = 17407896.

The previous prime is 20309213. The next prime is 20309243. The reversal of 20309219 is 91290302.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 91290302 = 2 ⋅45645151.

It is a cyclic number.

It is not a de Polignac number, because 20309219 - 2⁸ = 20308963 is a prime.

It is a super-2 number, since 2×20309219² = 824928752779922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20309213) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1450652 + ... + 1450665.

It is an arithmetic number, because the mean of its divisors is an integer number (5802636).

Almost surely, 2^20309219 is an apocalyptic number.

20309219 is a deficient number, since it is larger than the sum of its proper divisors (2901325).

20309219 is an equidigital number, since it uses as much as digits as its factorization.

20309219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2901324.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 20309219 is about 4506.5750853614. The cubic root of 20309219 is about 272.8335292663.

The spelling of 20309219 in words is "twenty million, three hundred nine thousand, two hundred nineteen".