81938132 has 6 divisors (see below), whose sum is σ = 143391738. Its totient is φ = 40969064.

The previous prime is 81938111. The next prime is 81938141. The reversal of 81938132 is 23183918.

It can be written as a sum of positive squares in only one way, i.e., 62188996 + 19749136 = 7886^2 + 4444^2 .

It is a junction number, because it is equal to n+sod(n) for n = 81938092 and 81938101.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10242263 + ... + 10242270.

It is an arithmetic number, because the mean of its divisors is an integer number (23898623).

Almost surely, 2^81938132 is an apocalyptic number.

It is an amenable number.

81938132 is a deficient number, since it is larger than the sum of its proper divisors (61453606).

81938132 is a wasteful number, since it uses less digits than its factorization.

81938132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20484537 (or 20484535 counting only the distinct ones).

The product of its digits is 10368, while the sum is 35.

The square root of 81938132 is about 9051.9684047173. The cubic root of 81938132 is about 434.3388591431.

The spelling of 81938132 in words is "eighty-one million, nine hundred thirty-eight thousand, one hundred thirty-two".