81478682 has 4 divisors (see below), whose sum is σ = 122218026. Its totient is φ = 40739340.

The previous prime is 81478667. The next prime is 81478687. The reversal of 81478682 is 28687418.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 28687418 = 2 ⋅14343709.

It can be written as a sum of positive squares in only one way, i.e., 48427681 + 33051001 = 6959^2 + 5749^2 .

It is not an unprimeable number, because it can be changed into a prime (81478687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20369669 + ... + 20369672.

Almost surely, 2^81478682 is an apocalyptic number.

81478682 is a deficient number, since it is larger than the sum of its proper divisors (40739344).

81478682 is a wasteful number, since it uses less digits than its factorization.

81478682 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40739343.

The product of its digits is 172032, while the sum is 44.

The square root of 81478682 is about 9026.5542705952. The cubic root of 81478682 is about 433.5255172519.

The spelling of 81478682 in words is "eighty-one million, four hundred seventy-eight thousand, six hundred eighty-two".