81700293 has 4 divisors (see below), whose sum is σ = 108933728. Its totient is φ = 54466860.

The previous prime is 81700291. The next prime is 81700343. The reversal of 81700293 is 39200718.

It is a happy number.

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 81700293 - 2¹ = 81700291 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81700293.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81700291) 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, 13616713 + ... + 13616718.

It is an arithmetic number, because the mean of its divisors is an integer number (27233432).

Almost surely, 2^81700293 is an apocalyptic number.

It is an amenable number.

81700293 is a deficient number, since it is larger than the sum of its proper divisors (27233435).

81700293 is a wasteful number, since it uses less digits than its factorization.

81700293 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27233434.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 81700293 is about 9038.8214386611. The cubic root of 81700293 is about 433.9182050472.

The spelling of 81700293 in words is "eighty-one million, seven hundred thousand, two hundred ninety-three".