20216730 has 16 divisors (see below), whose sum is σ = 48520224. Its totient is φ = 5391120.

The previous prime is 20216699. The next prime is 20216759. The reversal of 20216730 is 3761202.

It is a happy number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20216697 and 20216706.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 336916 + ... + 336975.

It is an arithmetic number, because the mean of its divisors is an integer number (3032514).

Almost surely, 2^20216730 is an apocalyptic number.

20216730 is an abundant number, since it is smaller than the sum of its proper divisors (28303494).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20216730 is a wasteful number, since it uses less digits than its factorization.

20216730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673901.

The product of its (nonzero) digits is 504, while the sum is 21.

The square root of 20216730 is about 4496.3018137131. The cubic root of 20216730 is about 272.4187340084.

Adding to 20216730 its reverse (3761202), we get a palindrome (23977932).

The spelling of 20216730 in words is "twenty million, two hundred sixteen thousand, seven hundred thirty".