81960648 has 64 divisors (see below), whose sum is σ = 255467520. Its totient is φ = 21288000.

The previous prime is 81960647. The next prime is 81960649. The reversal of 81960648 is 84606918.

It is an interprime number because it is at equal distance from previous prime (81960647) and next prime (81960649).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (81960647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20328 + ... + 24023.

It is an arithmetic number, because the mean of its divisors is an integer number (3991680).

Almost surely, 2^81960648 is an apocalyptic number.

81960648 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

81960648 is an abundant number, since it is smaller than the sum of its proper divisors (173506872).

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

81960648 is a wasteful number, since it uses less digits than its factorization.

81960648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44378 (or 44374 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 81960648 is about 9053.2120266787. The cubic root of 81960648 is about 434.3786398812.

The spelling of 81960648 in words is "eighty-one million, nine hundred sixty thousand, six hundred forty-eight".