81996285 has 16 divisors (see below), whose sum is σ = 149936256. Its totient is φ = 37483968.

The previous prime is 81996283. The next prime is 81996307. The reversal of 81996285 is 58269918.

It is a happy number.

It is not a de Polignac number, because 81996285 - 2¹ = 81996283 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81996283) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 390354 + ... + 390563.

It is an arithmetic number, because the mean of its divisors is an integer number (9371016).

Almost surely, 2^81996285 is an apocalyptic number.

It is an amenable number.

81996285 is a deficient number, since it is larger than the sum of its proper divisors (67939971).

81996285 is a wasteful number, since it uses less digits than its factorization.

81996285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 780932.

The product of its digits is 311040, while the sum is 48.

The square root of 81996285 is about 9055.1800092544. The cubic root of 81996285 is about 434.4415876043.

The spelling of 81996285 in words is "eighty-one million, nine hundred ninety-six thousand, two hundred eighty-five".