20720235 has 8 divisors (see below), whose sum is σ = 33152400. Its totient is φ = 11050784.

The previous prime is 20720221. The next prime is 20720237. The reversal of 20720235 is 53202702.

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

It is a cyclic number.

It is not a de Polignac number, because 20720235 - 2⁷ = 20720107 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20720237) 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, 690660 + ... + 690689.

It is an arithmetic number, because the mean of its divisors is an integer number (4144050).

Almost surely, 2^20720235 is an apocalyptic number.

20720235 is a deficient number, since it is larger than the sum of its proper divisors (12432165).

20720235 is a wasteful number, since it uses less digits than its factorization.

20720235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381357.

The product of its (nonzero) digits is 840, while the sum is 21.

The square root of 20720235 is about 4551.9484838913. The cubic root of 20720235 is about 274.6617770270.

Adding to 20720235 its reverse (53202702), we get a palindrome (73922937).

The spelling of 20720235 in words is "twenty million, seven hundred twenty thousand, two hundred thirty-five".