20720733 has 8 divisors (see below), whose sum is σ = 30139296. Its totient is φ = 12558000.

The previous prime is 20720731. The next prime is 20720743. The reversal of 20720733 is 33702702.

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

It is not a de Polignac number, because 20720733 - 2¹ = 20720731 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20720731) 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, 313918 + ... + 313983.

It is an arithmetic number, because the mean of its divisors is an integer number (3767412).

Almost surely, 2^20720733 is an apocalyptic number.

It is an amenable number.

20720733 is a deficient number, since it is larger than the sum of its proper divisors (9418563).

20720733 is a wasteful number, since it uses less digits than its factorization.

20720733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 627915.

The product of its (nonzero) digits is 1764, while the sum is 24.

The square root of 20720733 is about 4552.0031854119. The cubic root of 20720733 is about 274.6639774600.

The spelling of 20720733 in words is "twenty million, seven hundred twenty thousand, seven hundred thirty-three".