81936250486 has 4 divisors (see below), whose sum is σ = 122904375732. Its totient is φ = 40968125242.

The previous prime is 81936250469. The next prime is 81936250507. The reversal of 81936250486 is 68405263918.

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

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, 20484062620 + ... + 20484062623.

It is an arithmetic number, because the mean of its divisors is an integer number (30726093933).

Almost surely, 2^81936250486 is an apocalyptic number.

81936250486 is a deficient number, since it is larger than the sum of its proper divisors (40968125246).

81936250486 is a wasteful number, since it uses less digits than its factorization.

81936250486 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40968125245.

The product of its (nonzero) digits is 2488320, while the sum is 52.

The spelling of 81936250486 in words is "eighty-one billion, nine hundred thirty-six million, two hundred fifty thousand, four hundred eighty-six".