81584701 has 4 divisors (see below), whose sum is σ = 89001504. Its totient is φ = 74167900.

The previous prime is 81584693. The next prime is 81584729. The reversal of 81584701 is 10748518.

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 a cyclic number.

It is not a de Polignac number, because 81584701 - 2³ = 81584693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81584771) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3708385 + ... + 3708406.

It is an arithmetic number, because the mean of its divisors is an integer number (22250376).

Almost surely, 2^81584701 is an apocalyptic number.

It is an amenable number.

81584701 is a deficient number, since it is larger than the sum of its proper divisors (7416803).

81584701 is a wasteful number, since it uses less digits than its factorization.

81584701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7416802.

The product of its (nonzero) digits is 8960, while the sum is 34.

The square root of 81584701 is about 9032.4249789301. The cubic root of 81584701 is about 433.7134683415.

The spelling of 81584701 in words is "eighty-one million, five hundred eighty-four thousand, seven hundred one".