81186652 has 6 divisors (see below), whose sum is σ = 142076648. Its totient is φ = 40593324.

The previous prime is 81186643. The next prime is 81186653. The reversal of 81186652 is 25668118.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81186653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10148328 + ... + 10148335.

Almost surely, 2^81186652 is an apocalyptic number.

It is an amenable number.

81186652 is a deficient number, since it is larger than the sum of its proper divisors (60889996).

81186652 is a wasteful number, since it uses less digits than its factorization.

81186652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20296667 (or 20296665 counting only the distinct ones).

The product of its digits is 23040, while the sum is 37.

The square root of 81186652 is about 9010.3635886683. The cubic root of 81186652 is about 433.0069602965.

The spelling of 81186652 in words is "eighty-one million, one hundred eighty-six thousand, six hundred fifty-two".