81376321 has 8 divisors (see below), whose sum is σ = 87736320. Its totient is φ = 75030672.

The previous prime is 81376313. The next prime is 81376343. The reversal of 81376321 is 12367318.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81376321 - 2³ = 81376313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81376381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10176 + ... + 16318.

It is an arithmetic number, because the mean of its divisors is an integer number (10967040).

Almost surely, 2^81376321 is an apocalyptic number.

It is an amenable number.

81376321 is a deficient number, since it is larger than the sum of its proper divisors (6359999).

81376321 is a wasteful number, since it uses less digits than its factorization.

81376321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7175.

The product of its digits is 6048, while the sum is 31.

The square root of 81376321 is about 9020.8824956320. The cubic root of 81376321 is about 433.3438963237.

The spelling of 81376321 in words is "eighty-one million, three hundred seventy-six thousand, three hundred twenty-one".