81889652 has 24 divisors (see below), whose sum is σ = 154821576. Its totient is φ = 37675008.

The previous prime is 81889609. The next prime is 81889657. The reversal of 81889652 is 25698818.

It can be written as a sum of positive squares in 4 ways, for example, as 10588516 + 71301136 = 3254^2 + 8444^2 .

It is a super-2 number, since 2×81889652² = 13411830209362208, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81889597 and 81889606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81889657) 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, 15188 + ... + 19860.

It is an arithmetic number, because the mean of its divisors is an integer number (6450899).

Almost surely, 2^81889652 is an apocalyptic number.

It is an amenable number.

81889652 is a deficient number, since it is larger than the sum of its proper divisors (72931924).

81889652 is a wasteful number, since it uses less digits than its factorization.

81889652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5027 (or 5025 counting only the distinct ones).

The product of its digits is 276480, while the sum is 47.

The square root of 81889652 is about 9049.2901379058. The cubic root of 81889652 is about 434.2531810768.

The spelling of 81889652 in words is "eighty-one million, eight hundred eighty-nine thousand, six hundred fifty-two".