81746997 has 8 divisors (see below), whose sum is σ = 109174560. Its totient is φ = 54408720.

The previous prime is 81746981. The next prime is 81747019. The reversal of 81746997 is 79964718.

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

It is not a de Polignac number, because 81746997 - 2⁴ = 81746981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81746957) 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, 20154 + ... + 23867.

It is an arithmetic number, because the mean of its divisors is an integer number (13646820).

Almost surely, 2^81746997 is an apocalyptic number.

It is an amenable number.

81746997 is a deficient number, since it is larger than the sum of its proper divisors (27427563).

81746997 is a wasteful number, since it uses less digits than its factorization.

81746997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44643.

The product of its digits is 762048, while the sum is 51.

The square root of 81746997 is about 9041.4045922080. The cubic root of 81746997 is about 434.0008724596. Note that the first 3 decimals are identical.

The spelling of 81746997 in words is "eighty-one million, seven hundred forty-six thousand, nine hundred ninety-seven".