20720357 has 16 divisors (see below), whose sum is σ = 24307200. Its totient is φ = 17297280.

The previous prime is 20720347. The next prime is 20720363. The reversal of 20720357 is 75302702.

It is not a de Polignac number, because 20720357 - 2⁴ = 20720341 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20720327) 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 15 ways as a sum of consecutive naturals, for example, 49007 + ... + 49427.

It is an arithmetic number, because the mean of its divisors is an integer number (1519200).

Almost surely, 2^20720357 is an apocalyptic number.

It is an amenable number.

20720357 is a deficient number, since it is larger than the sum of its proper divisors (3586843).

20720357 is an equidigital number, since it uses as much as digits as its factorization.

20720357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 596.

The product of its (nonzero) digits is 2940, while the sum is 26.

The square root of 20720357 is about 4551.9618847262. The cubic root of 20720357 is about 274.6623160922.

The spelling of 20720357 in words is "twenty million, seven hundred twenty thousand, three hundred fifty-seven".