20910572167 has 4 divisors (see below), whose sum is σ = 20911444416. Its totient is φ = 20909699920.

The previous prime is 20910572129. The next prime is 20910572201. The reversal of 20910572167 is 76127501902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76127501902 = 2 ⋅38063750951.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20910572167 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 (20910570167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 399118 + ... + 448459.

It is an arithmetic number, because the mean of its divisors is an integer number (5227861104).

Almost surely, 2^20910572167 is an apocalyptic number.

20910572167 is a deficient number, since it is larger than the sum of its proper divisors (872249).

20910572167 is an equidigital number, since it uses as much as digits as its factorization.

20910572167 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 872248.

The product of its (nonzero) digits is 52920, while the sum is 40.

The spelling of 20910572167 in words is "twenty billion, nine hundred ten million, five hundred seventy-two thousand, one hundred sixty-seven".