19010820811 has 4 divisors (see below), whose sum is σ = 19012333824. Its totient is φ = 19009307800.

The previous prime is 19010820781. The next prime is 19010820827. The reversal of 19010820811 is 11802801091.

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 19010820811 - 2¹¹ = 19010818763 is a prime.

It is a super-2 number, since 2×19010820811² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19010820841) 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, 737500 + ... + 762841.

It is an arithmetic number, because the mean of its divisors is an integer number (4753083456).

Almost surely, 2^19010820811 is an apocalyptic number.

19010820811 is a deficient number, since it is larger than the sum of its proper divisors (1513013).

19010820811 is a wasteful number, since it uses less digits than its factorization.

19010820811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1513012.

The product of its (nonzero) digits is 1152, while the sum is 31.

The spelling of 19010820811 in words is "nineteen billion, ten million, eight hundred twenty thousand, eight hundred eleven".