81692226 has 192 divisors, whose sum is σ = 239016960. Its totient is φ = 20295360.

The previous prime is 81692207. The next prime is 81692227. The reversal of 81692226 is 62229618.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81692227) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1384585 + ... + 1384643.

It is an arithmetic number, because the mean of its divisors is an integer number (1244880).

Almost surely, 2^81692226 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81692226, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119508480).

81692226 is an abundant number, since it is smaller than the sum of its proper divisors (157324734).

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

81692226 is a wasteful number, since it uses less digits than its factorization.

81692226 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131 (or 119 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 81692226 is about 9038.3751858395. The cubic root of 81692226 is about 433.9039230365.

It can be divided in two parts, 81692 and 226, that added together give a palindrome (81918).

The spelling of 81692226 in words is "eighty-one million, six hundred ninety-two thousand, two hundred twenty-six".