20840164351 has 4 divisors (see below), whose sum is σ = 20926638304. Its totient is φ = 20753690400.

The previous prime is 20840164309. The next prime is 20840164393. The reversal of 20840164351 is 15346104802.

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

It is an interprime number because it is at equal distance from previous prime (20840164309) and next prime (20840164393).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20840164351 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 (20840167351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43236615 + ... + 43237096.

It is an arithmetic number, because the mean of its divisors is an integer number (5231659576).

Almost surely, 2^20840164351 is an apocalyptic number.

20840164351 is a deficient number, since it is larger than the sum of its proper divisors (86473953).

20840164351 is an equidigital number, since it uses as much as digits as its factorization.

20840164351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86473952.

The product of its (nonzero) digits is 23040, while the sum is 34.

The spelling of 20840164351 in words is "twenty billion, eight hundred forty million, one hundred sixty-four thousand, three hundred fifty-one".