81701873 has 4 divisors (see below), whose sum is σ = 89129328. Its totient is φ = 74274420.

The previous prime is 81701869. The next prime is 81701887. The reversal of 81701873 is 37810718.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 81701873 - 2² = 81701869 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81701863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3713711 + ... + 3713732.

It is an arithmetic number, because the mean of its divisors is an integer number (22282332).

Almost surely, 2^81701873 is an apocalyptic number.

81701873 is the 4832-nd centered heptagonal number.

It is an amenable number.

81701873 is a deficient number, since it is larger than the sum of its proper divisors (7427455).

81701873 is a wasteful number, since it uses less digits than its factorization.

81701873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7427454.

The product of its (nonzero) digits is 9408, while the sum is 35.

The square root of 81701873 is about 9038.9088390137. The cubic root of 81701873 is about 433.9210022071.

The spelling of 81701873 in words is "eighty-one million, seven hundred one thousand, eight hundred seventy-three".