81628152 has 64 divisors (see below), whose sum is σ = 219801600. Its totient is φ = 25167360.

The previous prime is 81628139. The next prime is 81628153. The reversal of 81628152 is 25182618.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81628153) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22377 + ... + 25767.

It is an arithmetic number, because the mean of its divisors is an integer number (3434400).

Almost surely, 2^81628152 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 81628152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109900800).

81628152 is an abundant number, since it is smaller than the sum of its proper divisors (138173448).

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

81628152 is a wasteful number, since it uses less digits than its factorization.

81628152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3476 (or 3472 counting only the distinct ones).

The product of its digits is 7680, while the sum is 33.

The square root of 81628152 is about 9034.8299375251. The cubic root of 81628152 is about 433.7904514813.

The spelling of 81628152 in words is "eighty-one million, six hundred twenty-eight thousand, one hundred fifty-two".