20289545 has 4 divisors (see below), whose sum is σ = 24347460. Its totient is φ = 16231632.

The previous prime is 20289541. The next prime is 20289553. The reversal of 20289545 is 54598202.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54598202 = 2 ⋅27299101.

It can be written as a sum of positive squares in 2 ways, for example, as 9504889 + 10784656 = 3083^2 + 3284^2 .

It is a cyclic number.

It is not a de Polignac number, because 20289545 - 2² = 20289541 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20289541) 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, 2028950 + ... + 2028959.

It is an arithmetic number, because the mean of its divisors is an integer number (6086865).

Almost surely, 2^20289545 is an apocalyptic number.

It is an amenable number.

20289545 is a deficient number, since it is larger than the sum of its proper divisors (4057915).

20289545 is an equidigital number, since it uses as much as digits as its factorization.

20289545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4057914.

The product of its (nonzero) digits is 28800, while the sum is 35.

The square root of 20289545 is about 4504.3917458409. The cubic root of 20289545 is about 272.7454007984.

The spelling of 20289545 in words is "twenty million, two hundred eighty-nine thousand, five hundred forty-five".