81894058 has 4 divisors (see below), whose sum is σ = 122841090. Its totient is φ = 40947028.

The previous prime is 81894041. The next prime is 81894073. The reversal of 81894058 is 85049818.

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., 47706649 + 34187409 = 6907^2 + 5847^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20473513 + ... + 20473516.

Almost surely, 2^81894058 is an apocalyptic number.

81894058 is a deficient number, since it is larger than the sum of its proper divisors (40947032).

81894058 is a wasteful number, since it uses less digits than its factorization.

81894058 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40947031.

The product of its (nonzero) digits is 92160, while the sum is 43.

The square root of 81894058 is about 9049.5335791410. The cubic root of 81894058 is about 434.2609691394.

The spelling of 81894058 in words is "eighty-one million, eight hundred ninety-four thousand, fifty-eight".