20989176311 has 4 divisors (see below), whose sum is σ = 20989482912. Its totient is φ = 20988869712.

The previous prime is 20989176283. The next prime is 20989176353. The reversal of 20989176311 is 11367198902.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 11367198902 = 2 ⋅5683599451.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20989176311 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 (20989178311) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1475 + ... + 204891.

It is an arithmetic number, because the mean of its divisors is an integer number (5247370728).

Almost surely, 2^20989176311 is an apocalyptic number.

20989176311 is a deficient number, since it is larger than the sum of its proper divisors (306601).

20989176311 is a wasteful number, since it uses less digits than its factorization.

20989176311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306600.

The product of its (nonzero) digits is 163296, while the sum is 47.

The spelling of 20989176311 in words is "twenty billion, nine hundred eighty-nine million, one hundred seventy-six thousand, three hundred eleven".