81970766357 has 8 divisors (see below), whose sum is σ = 83428896480. Its totient is φ = 80514929520.

The previous prime is 81970766341. The next prime is 81970766369. The reversal of 81970766357 is 75366707918.

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 81970766357 - 2⁴ = 81970766341 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (59).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81970766296 and 81970766305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81970766327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 501119 + ... + 644252.

It is an arithmetic number, because the mean of its divisors is an integer number (10428612060).

Almost surely, 2^81970766357 is an apocalyptic number.

It is an amenable number.

81970766357 is a deficient number, since it is larger than the sum of its proper divisors (1458130123).

81970766357 is a wasteful number, since it uses less digits than its factorization.

81970766357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1146643.

The product of its (nonzero) digits is 13335840, while the sum is 59.

The spelling of 81970766357 in words is "eighty-one billion, nine hundred seventy million, seven hundred sixty-six thousand, three hundred fifty-seven".