81980693077 has 8 divisors (see below), whose sum is σ = 82905825600. Its totient is φ = 81058045440.

The previous prime is 81980693071. The next prime is 81980693083. The reversal of 81980693077 is 77039608918.

It is an interprime number because it is at equal distance from previous prime (81980693071) and next prime (81980693083).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81980693077 - 2¹¹ = 81980691029 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 (81980693071) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 554827 + ... + 686872.

It is an arithmetic number, because the mean of its divisors is an integer number (10363228200).

Almost surely, 2^81980693077 is an apocalyptic number.

It is an amenable number.

81980693077 is a deficient number, since it is larger than the sum of its proper divisors (925132523).

81980693077 is a wasteful number, since it uses less digits than its factorization.

81980693077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1242443.

The product of its (nonzero) digits is 4572288, while the sum is 58.

The spelling of 81980693077 in words is "eighty-one billion, nine hundred eighty million, six hundred ninety-three thousand, seventy-seven".