81807262 has 4 divisors (see below), whose sum is σ = 122710896. Its totient is φ = 40903630.

The previous prime is 81807223. The next prime is 81807263. The reversal of 81807262 is 26270818.

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

It is a super-3 number, since 3×81807262³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81807263) 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 as a sum of consecutive naturals, namely, 20451814 + ... + 20451817.

It is an arithmetic number, because the mean of its divisors is an integer number (30677724).

Almost surely, 2^81807262 is an apocalyptic number.

81807262 is a deficient number, since it is larger than the sum of its proper divisors (40903634).

81807262 is a wasteful number, since it uses less digits than its factorization.

81807262 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40903633.

The product of its (nonzero) digits is 10752, while the sum is 34.

The square root of 81807262 is about 9044.7367015298. The cubic root of 81807262 is about 434.1074967144.

The spelling of 81807262 in words is "eighty-one million, eight hundred seven thousand, two hundred sixty-two".