81819465767 has 16 divisors (see below), whose sum is σ = 93308785920. Its totient is φ = 71073541632.

The previous prime is 81819465757. The next prime is 81819465769. The reversal of 81819465767 is 76756491818.

It is a cyclic number.

It is not a de Polignac number, because 81819465767 - 2⁴ = 81819465751 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 (81819465769) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2033834 + ... + 2073672.

It is an arithmetic number, because the mean of its divisors is an integer number (5831799120).

Almost surely, 2^81819465767 is an apocalyptic number.

81819465767 is a deficient number, since it is larger than the sum of its proper divisors (11489320153).

81819465767 is a wasteful number, since it uses less digits than its factorization.

81819465767 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49162.

The product of its digits is 20321280, while the sum is 62.

The spelling of 81819465767 in words is "eighty-one billion, eight hundred nineteen million, four hundred sixty-five thousand, seven hundred sixty-seven".