81342361 has 9 divisors (see below), whose sum is σ = 84515743. Its totient is φ = 78284920.

The previous prime is 81342337. The next prime is 81342377. The reversal of 81342361 is 16324318.

The square root of 81342361 is 9019.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 42653961 + 38688400 = 6531^2 + 6220^2 .

It is not a de Polignac number, because 81342361 - 2¹¹ = 81340313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81342461) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 261396 + ... + 261706.

Almost surely, 2^81342361 is an apocalyptic number.

81342361 is the 9019-th square number.

81342361 is the 4510-th centered octagonal number.

It is an amenable number.

81342361 is a deficient number, since it is larger than the sum of its proper divisors (3173382).

81342361 is an frugal number, since it uses more digits than its factorization.

81342361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 680 (or 340 counting only the distinct ones).

The product of its digits is 3456, while the sum is 28.

The cubic root of 81342361 is about 433.2836068515.

Adding to 81342361 its reverse (16324318), we get a palindrome (97666679).

The spelling of 81342361 in words is "eighty-one million, three hundred forty-two thousand, three hundred sixty-one".