81083642 has 8 divisors (see below), whose sum is σ = 128779956. Its totient is φ = 38156992.

The previous prime is 81083627. The next prime is 81083647. The reversal of 81083642 is 24638018.

It can be written as a sum of positive squares in 2 ways, for example, as 78836641 + 2247001 = 8879^2 + 1499^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 81083599 and 81083608.

It is not an unprimeable number, because it can be changed into a prime (81083647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1192373 + ... + 1192440.

Almost surely, 2^81083642 is an apocalyptic number.

81083642 is a deficient number, since it is larger than the sum of its proper divisors (47696314).

81083642 is a wasteful number, since it uses less digits than its factorization.

81083642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2384832.

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 81083642 is about 9004.6455788110. The cubic root of 81083642 is about 432.8237490427.

The spelling of 81083642 in words is "eighty-one million, eighty-three thousand, six hundred forty-two".