81420716111 has 4 divisors (see below), whose sum is σ = 93052246992. Its totient is φ = 69789185232.

The previous prime is 81420716101. The next prime is 81420716149. The reversal of 81420716111 is 11161702418.

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 81420716111 - 2¹⁰ = 81420715087 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 (81420716101) 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, 5815765430 + ... + 5815765443.

It is an arithmetic number, because the mean of its divisors is an integer number (23263061748).

Almost surely, 2^81420716111 is an apocalyptic number.

81420716111 is a deficient number, since it is larger than the sum of its proper divisors (11631530881).

81420716111 is a wasteful number, since it uses less digits than its factorization.

81420716111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11631530880.

The product of its (nonzero) digits is 2688, while the sum is 32.

The spelling of 81420716111 in words is "eighty-one billion, four hundred twenty million, seven hundred sixteen thousand, one hundred eleven".