81397086 has 16 divisors (see below), whose sum is σ = 164624400. Its totient is φ = 26827328.

The previous prime is 81397081. The next prime is 81397109. The reversal of 81397086 is 68079318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81397081) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 75681 + ... + 76748.

It is an arithmetic number, because the mean of its divisors is an integer number (10289025).

Almost surely, 2^81397086 is an apocalyptic number.

81397086 is an abundant number, since it is smaller than the sum of its proper divisors (83227314).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81397086 is a wasteful number, since it uses less digits than its factorization.

81397086 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152523.

The product of its (nonzero) digits is 72576, while the sum is 42.

The square root of 81397086 is about 9022.0333628290. The cubic root of 81397086 is about 433.3807523388.

It can be divided in two parts, 8139 and 7086, that added together give a triangular number (15225 = T₁₇₄).

The spelling of 81397086 in words is "eighty-one million, three hundred ninety-seven thousand, eighty-six".