81676644 has 48 divisors (see below), whose sum is σ = 225321600. Its totient is φ = 22530816.

The previous prime is 81676627. The next prime is 81676667. The reversal of 81676644 is 44667618.

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

It is a junction number, because it is equal to n+sod(n) for n = 81676596 and 81676605.

It is an unprimeable number.

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, 14329 + ... + 19200.

It is an arithmetic number, because the mean of its divisors is an integer number (4694200).

Almost surely, 2^81676644 is an apocalyptic number.

81676644 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

81676644 is an abundant number, since it is smaller than the sum of its proper divisors (143644956).

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

81676644 is a wasteful number, since it uses less digits than its factorization.

81676644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33572 (or 33570 counting only the distinct ones).

The product of its digits is 193536, while the sum is 42.

The square root of 81676644 is about 9037.5131535174. The cubic root of 81676644 is about 433.8763336270.

The spelling of 81676644 in words is "eighty-one million, six hundred seventy-six thousand, six hundred forty-four".