81610617 has 8 divisors (see below), whose sum is σ = 118706400. Its totient is φ = 49460960.

The previous prime is 81610609. The next prime is 81610679. The reversal of 81610617 is 71601618.

It is a happy number.

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 81610617 - 2³ = 81610609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81610687) 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, 1236492 + ... + 1236557.

It is an arithmetic number, because the mean of its divisors is an integer number (14838300).

Almost surely, 2^81610617 is an apocalyptic number.

It is an amenable number.

81610617 is a deficient number, since it is larger than the sum of its proper divisors (37095783).

81610617 is a wasteful number, since it uses less digits than its factorization.

81610617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2473063.

The product of its (nonzero) digits is 2016, while the sum is 30.

The square root of 81610617 is about 9033.8594742225. The cubic root of 81610617 is about 433.7593876056.

The spelling of 81610617 in words is "eighty-one million, six hundred ten thousand, six hundred seventeen".