20919077801 has 4 divisors (see below), whose sum is σ = 20936792004. Its totient is φ = 20901363600.

The previous prime is 20919077771. The next prime is 20919077807. The reversal of 20919077801 is 10877091902.

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

It can be written as a sum of positive squares in 2 ways, for example, as 16631971225 + 4287106576 = 128965^2 + 65476^2 .

It is a cyclic number.

It is not a de Polignac number, because 20919077801 - 2¹⁰ = 20919076777 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20919077807) 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, 8855330 + ... + 8857691.

It is an arithmetic number, because the mean of its divisors is an integer number (5234198001).

Almost surely, 2^20919077801 is an apocalyptic number.

It is an amenable number.

20919077801 is a deficient number, since it is larger than the sum of its proper divisors (17714203).

20919077801 is a wasteful number, since it uses less digits than its factorization.

20919077801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17714202.

The product of its (nonzero) digits is 63504, while the sum is 44.

The spelling of 20919077801 in words is "twenty billion, nine hundred nineteen million, seventy-seven thousand, eight hundred one".