20289506 has 8 divisors (see below), whose sum is σ = 31176684. Its totient is φ = 9897280.

The previous prime is 20289497. The next prime is 20289509. The reversal of 20289506 is 60598202.

It can be written as a sum of positive squares in 2 ways, for example, as 19404025 + 885481 = 4405^2 + 941^2 .

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

It is not an unprimeable number, because it can be changed into a prime (20289509) 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, 123635 + ... + 123798.

Almost surely, 2^20289506 is an apocalyptic number.

20289506 is a deficient number, since it is larger than the sum of its proper divisors (10887178).

20289506 is a wasteful number, since it uses less digits than its factorization.

20289506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247476.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 20289506 is about 4504.3874167305. The cubic root of 20289506 is about 272.7452260437.

The spelling of 20289506 in words is "twenty million, two hundred eighty-nine thousand, five hundred six".