81655948390280 has 96 divisors (see below), whose sum is σ = 206643066537600. Its totient is φ = 29002535506560.

The previous prime is 81655948390273. The next prime is 81655948390339. The reversal of 81655948390280 is 8209384955618.

It is a super-3 number, since 3×81655948390280³ (a number of 43 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81655948390280.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 195967040 + ... + 196383279.

It is an arithmetic number, because the mean of its divisors is an integer number (2152531943100).

Almost surely, 2^{81655948390280} is an apocalyptic number.

It is an amenable number.

81655948390280 is an abundant number, since it is smaller than the sum of its proper divisors (124987118147320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81655948390280 is a wasteful number, since it uses less digits than its factorization.

81655948390280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392350395 (or 392350380 counting only the distinct ones).

The product of its (nonzero) digits is 149299200, while the sum is 68.

The spelling of 81655948390280 in words is "eighty-one trillion, six hundred fifty-five billion, nine hundred forty-eight million, three hundred ninety thousand, two hundred eighty".