16820013 has 8 divisors (see below), whose sum is σ = 25630528. Its totient is φ = 9611424.

The previous prime is 16819993. The next prime is 16820017. The reversal of 16820013 is 31002861.

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

It is not a de Polignac number, because 16820013 - 2⁵ = 16819981 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 800953 = 16820013 / (1 + 6 + 8 + 2 + 0 + 0 + 1 + 3).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16820017) 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, 400456 + ... + 400497.

It is an arithmetic number, because the mean of its divisors is an integer number (3203816).

Almost surely, 2^16820013 is an apocalyptic number.

It is an amenable number.

16820013 is a deficient number, since it is larger than the sum of its proper divisors (8810515).

16820013 is an equidigital number, since it uses as much as digits as its factorization.

16820013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800963.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 16820013 is about 4101.2209157762. The cubic root of 16820013 is about 256.2174919698.

Adding to 16820013 its reverse (31002861), we get a palindrome (47822874).

The spelling of 16820013 in words is "sixteen million, eight hundred twenty thousand, thirteen".