81266064 has 40 divisors (see below), whose sum is σ = 229024032. Its totient is φ = 24625920.

The previous prime is 81266063. The next prime is 81266077. The reversal of 81266064 is 46066218.

It is a happy number.

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 (81266063) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76429 + ... + 77484.

Almost surely, 2^81266064 is an apocalyptic number.

It is an amenable number.

81266064 is an abundant number, since it is smaller than the sum of its proper divisors (147757968).

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

81266064 is a wasteful number, since it uses less digits than its factorization.

81266064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153935 (or 153929 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 81266064 is about 9014.7692150160. The cubic root of 81266064 is about 433.1480949228.

The spelling of 81266064 in words is "eighty-one million, two hundred sixty-six thousand, sixty-four".