20678811 has 4 divisors (see below), whose sum is σ = 27571752. Its totient is φ = 13785872.

The previous prime is 20678809. The next prime is 20678831. The reversal of 20678811 is 11887602.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20678811 - 2¹ = 20678809 is a prime.

It is a super-2 number, since 2×20678811² = 855226448747442, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20678831) 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 3 ways as a sum of consecutive naturals, for example, 3446466 + ... + 3446471.

It is an arithmetic number, because the mean of its divisors is an integer number (6892938).

Almost surely, 2^20678811 is an apocalyptic number.

20678811 is a deficient number, since it is larger than the sum of its proper divisors (6892941).

20678811 is an equidigital number, since it uses as much as digits as its factorization.

20678811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6892940.

The product of its (nonzero) digits is 5376, while the sum is 33.

The square root of 20678811 is about 4547.3960680812. The cubic root of 20678811 is about 274.4786198390.

It can be divided in two parts, 2067 and 8811, that added together give a triangular number (10878 = T₁₄₇).

The spelling of 20678811 in words is "twenty million, six hundred seventy-eight thousand, eight hundred eleven".