81678026 has 4 divisors (see below), whose sum is σ = 122517042. Its totient is φ = 40839012.

The previous prime is 81678001. The next prime is 81678031. The reversal of 81678026 is 62087618.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 74839801 + 6838225 = 8651^2 + 2615^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20419505 + ... + 20419508.

Almost surely, 2^81678026 is an apocalyptic number.

81678026 is a deficient number, since it is larger than the sum of its proper divisors (40839016).

81678026 is a wasteful number, since it uses less digits than its factorization.

81678026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40839015.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 81678026 is about 9037.5896122805. The cubic root of 81678026 is about 433.8787807309.

The spelling of 81678026 in words is "eighty-one million, six hundred seventy-eight thousand, twenty-six".