20720318 has 8 divisors (see below), whose sum is σ = 31101840. Its totient is φ = 10353040.

The previous prime is 20720311. The next prime is 20720321. The reversal of 20720318 is 81302702.

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

It is a super-2 number, since 2×20720318² = 858663156042248, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20720293 and 20720302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20720311) 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, 1538 + ... + 6618.

It is an arithmetic number, because the mean of its divisors is an integer number (3887730).

Almost surely, 2^20720318 is an apocalyptic number.

20720318 is a deficient number, since it is larger than the sum of its proper divisors (10381522).

20720318 is a wasteful number, since it uses less digits than its factorization.

20720318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7122.

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 20720318 is about 4551.9576008570. The cubic root of 20720318 is about 274.6621437683.

The spelling of 20720318 in words is "twenty million, seven hundred twenty thousand, three hundred eighteen".