20645319 has 4 divisors (see below), whose sum is σ = 27527096. Its totient is φ = 13763544.

The previous prime is 20645311. The next prime is 20645321. The reversal of 20645319 is 91354602.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20645319 - 2³ = 20645311 is a prime.

It is a super-2 number, since 2×20645319² = 852458393223522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20645311) by changing a digit.

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, 3440884 + ... + 3440889.

It is an arithmetic number, because the mean of its divisors is an integer number (6881774).

Almost surely, 2^20645319 is an apocalyptic number.

20645319 is a deficient number, since it is larger than the sum of its proper divisors (6881777).

20645319 is an equidigital number, since it uses as much as digits as its factorization.

20645319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6881776.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 20645319 is about 4543.7120287272. The cubic root of 20645319 is about 274.3303552636.

The spelling of 20645319 in words is "twenty million, six hundred forty-five thousand, three hundred nineteen".