20290345 has 8 divisors (see below), whose sum is σ = 24398280. Its totient is φ = 16199040.

The previous prime is 20290331. The next prime is 20290349. The reversal of 20290345 is 54309202.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 1315609 + 18974736 = 1147^2 + 4356^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20290345 - 2⁷ = 20290217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20290349) 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 7 ways as a sum of consecutive naturals, for example, 1290 + ... + 6499.

It is an arithmetic number, because the mean of its divisors is an integer number (3049785).

Almost surely, 2^20290345 is an apocalyptic number.

It is an amenable number.

20290345 is a deficient number, since it is larger than the sum of its proper divisors (4107935).

20290345 is an equidigital number, since it uses as much as digits as its factorization.

20290345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8315.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 20290345 is about 4504.4805471885. The cubic root of 20290345 is about 272.7489854599.

Adding to 20290345 its reverse (54309202), we get a palindrome (74599547).

The spelling of 20290345 in words is "twenty million, two hundred ninety thousand, three hundred forty-five".