81213057327 has 4 divisors (see below), whose sum is σ = 108284076440. Its totient is φ = 54142038216.

The previous prime is 81213057307. The next prime is 81213057347. The reversal of 81213057327 is 72375031218.

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

It is an interprime number because it is at equal distance from previous prime (81213057307) and next prime (81213057347).

It is not a de Polignac number, because 81213057327 - 2¹⁴ = 81213040943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81213057307) 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, 13535509552 + ... + 13535509557.

It is an arithmetic number, because the mean of its divisors is an integer number (27071019110).

Almost surely, 2^81213057327 is an apocalyptic number.

81213057327 is a deficient number, since it is larger than the sum of its proper divisors (27071019113).

81213057327 is a wasteful number, since it uses less digits than its factorization.

81213057327 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27071019112.

The product of its (nonzero) digits is 70560, while the sum is 39.

The spelling of 81213057327 in words is "eighty-one billion, two hundred thirteen million, fifty-seven thousand, three hundred twenty-seven".