81290284 has 12 divisors (see below), whose sum is σ = 149745400. Its totient is φ = 38505888.

The previous prime is 81290281. The next prime is 81290291. The reversal of 81290284 is 48209218.

It is a super-2 number, since 2×81290284² = 13216220545601312, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81290281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 534729 + ... + 534880.

Almost surely, 2^81290284 is an apocalyptic number.

It is an amenable number.

81290284 is a deficient number, since it is larger than the sum of its proper divisors (68455116).

81290284 is a wasteful number, since it uses less digits than its factorization.

81290284 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1069632 (or 1069630 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 81290284 is about 9016.1124660244. The cubic root of 81290284 is about 433.1911215127.

The spelling of 81290284 in words is "eighty-one million, two hundred ninety thousand, two hundred eighty-four".