71819664 has 160 divisors (see below), whose sum is σ = 223914240. Its totient is φ = 19408896.

The previous prime is 71819623. The next prime is 71819669. The reversal of 71819664 is 46691817.

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 (71819669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 658842 + ... + 658950.

It is an arithmetic number, because the mean of its divisors is an integer number (1399464).

Almost surely, 2^71819664 is an apocalyptic number.

71819664 is a gapful number since it is divisible by the number (74) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71819664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111957120).

71819664 is an abundant number, since it is smaller than the sum of its proper divisors (152094576).

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

71819664 is a wasteful number, since it uses less digits than its factorization.

71819664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217 (or 211 counting only the distinct ones).

The product of its digits is 72576, while the sum is 42.

The square root of 71819664 is about 8474.6483112870. The cubic root of 71819664 is about 415.6691464517.

The spelling of 71819664 in words is "seventy-one million, eight hundred nineteen thousand, six hundred sixty-four".