81214170361 has 27 divisors (see below), whose sum is σ = 87671109519. Its totient is φ = 75221304912.

The previous prime is 81214170353. The next prime is 81214170379. The reversal of 81214170361 is 16307141218.

The square root of 81214170361 is 284981.

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., 58547061225 + 22667109136 = 241965^2 + 150556^2 .

It is not a de Polignac number, because 81214170361 - 2³ = 81214170353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81214170311) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 286975726 + ... + 286976008.

Almost surely, 2^81214170361 is an apocalyptic number.

81214170361 is the 284981-st square number.

81214170361 is the 142491-st centered octagonal number.

It is an amenable number.

81214170361 is a deficient number, since it is larger than the sum of its proper divisors (6456939158).

81214170361 is an frugal number, since it uses more digits than its factorization.

81214170361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 710 (or 355 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 34.

The spelling of 81214170361 in words is "eighty-one billion, two hundred fourteen million, one hundred seventy thousand, three hundred sixty-one".