81244276 has 6 divisors (see below), whose sum is σ = 142177490. Its totient is φ = 40622136.

The previous prime is 81244271. The next prime is 81244279. The reversal of 81244276 is 67244218.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 78747876 + 2496400 = 8874^2 + 1580^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81244271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10155531 + ... + 10155538.

Almost surely, 2^81244276 is an apocalyptic number.

It is an amenable number.

81244276 is a deficient number, since it is larger than the sum of its proper divisors (60933214).

81244276 is a wasteful number, since it uses less digits than its factorization.

81244276 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20311073 (or 20311071 counting only the distinct ones).

The product of its digits is 21504, while the sum is 34.

The square root of 81244276 is about 9013.5606726754. The cubic root of 81244276 is about 433.1093814518.

The spelling of 81244276 in words is "eighty-one million, two hundred forty-four thousand, two hundred seventy-six".