20311385 has 8 divisors (see below), whose sum is σ = 24737856. Its totient is φ = 16006320.

The previous prime is 20311381. The next prime is 20311433. The reversal of 20311385 is 58311302.

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

It is not a de Polignac number, because 20311385 - 2² = 20311381 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20311385.

It is not an unprimeable number, because it can be changed into a prime (20311381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29981 + ... + 30650.

It is an arithmetic number, because the mean of its divisors is an integer number (3092232).

Almost surely, 2^20311385 is an apocalyptic number.

It is an amenable number.

20311385 is a deficient number, since it is larger than the sum of its proper divisors (4426471).

20311385 is an equidigital number, since it uses as much as digits as its factorization.

20311385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60703.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 20311385 is about 4506.8153944887. The cubic root of 20311385 is about 272.8432282511.

Adding to 20311385 its reverse (58311302), we get a palindrome (78622687).

The spelling of 20311385 in words is "twenty million, three hundred eleven thousand, three hundred eighty-five".