81748992 has 176 divisors, whose sum is σ = 247605120. Its totient is φ = 23789568.

The previous prime is 81748991. The next prime is 81748993. The reversal of 81748992 is 29984718.

It is an interprime number because it is at equal distance from previous prime (81748991) and next prime (81748993).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (81748991) 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 15 ways as a sum of consecutive naturals, for example, 918484 + ... + 918572.

Almost surely, 2^81748992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81748992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123802560).

81748992 is an abundant number, since it is smaller than the sum of its proper divisors (165856128).

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

81748992 is a wasteful number, since it uses less digits than its factorization.

81748992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148 (or 130 counting only the distinct ones).

The product of its digits is 290304, while the sum is 48.

The square root of 81748992 is about 9041.5149173134. The cubic root of 81748992 is about 434.0044029652.

The spelling of 81748992 in words is "eighty-one million, seven hundred forty-eight thousand, nine hundred ninety-two".