81562272 has 48 divisors (see below), whose sum is σ = 233567712. Its totient is φ = 24715520.

The previous prime is 81562259. The next prime is 81562279. The reversal of 81562272 is 27226518.

It is a tau number, because it is divible by the number of its divisors (48).

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (81562279) 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 7 ways as a sum of consecutive naturals, for example, 37563 + ... + 39674.

It is an arithmetic number, because the mean of its divisors is an integer number (4865994).

Almost surely, 2^81562272 is an apocalyptic number.

It is an amenable number.

81562272 is an abundant number, since it is smaller than the sum of its proper divisors (152005440).

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

81562272 is a wasteful number, since it uses less digits than its factorization.

81562272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77261 (or 77253 counting only the distinct ones).

The product of its digits is 13440, while the sum is 33.

The square root of 81562272 is about 9031.1833111725. The cubic root of 81562272 is about 433.6737196679.

The spelling of 81562272 in words is "eighty-one million, five hundred sixty-two thousand, two hundred seventy-two".