81705552 has 40 divisors (see below), whose sum is σ = 215569536. Its totient is φ = 26654976.

The previous prime is 81705551. The next prime is 81705563. The reversal of 81705552 is 25550718.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81705551) 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, 15853 + ... + 20364.

Almost surely, 2^81705552 is an apocalyptic number.

It is an amenable number.

81705552 is an abundant number, since it is smaller than the sum of its proper divisors (133863984).

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

81705552 is a wasteful number, since it uses less digits than its factorization.

81705552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36275 (or 36269 counting only the distinct ones).

The product of its (nonzero) digits is 14000, while the sum is 33.

The square root of 81705552 is about 9039.1123458003. The cubic root of 81705552 is about 433.9275152010.

The spelling of 81705552 in words is "eighty-one million, seven hundred five thousand, five hundred fifty-two".