81935541 has 6 divisors (see below), whose sum is σ = 118351350. Its totient is φ = 54623688.

The previous prime is 81935531. The next prime is 81935551. The reversal of 81935541 is 14553918.

81935541 is a `hidden beast` number, since 81 + 9 + 35 + 541 = 666.

It is an interprime number because it is at equal distance from previous prime (81935531) and next prime (81935551).

It can be written as a sum of positive squares in only one way, i.e., 46580625 + 35354916 = 6825^2 + 5946^2 .

It is not a de Polignac number, because 81935541 - 2²¹ = 79838389 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81935496 and 81935505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81935521) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4551966 + ... + 4551983.

It is an arithmetic number, because the mean of its divisors is an integer number (19725225).

Almost surely, 2^81935541 is an apocalyptic number.

It is an amenable number.

81935541 is a deficient number, since it is larger than the sum of its proper divisors (36415809).

81935541 is a wasteful number, since it uses less digits than its factorization.

81935541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9103955 (or 9103952 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 81935541 is about 9051.8252855432. The cubic root of 81935541 is about 434.3342809578.

The spelling of 81935541 in words is "eighty-one million, nine hundred thirty-five thousand, five hundred forty-one".