81353743 has 8 divisors (see below), whose sum is σ = 83667600. Its totient is φ = 79071168.

The previous prime is 81353731. The next prime is 81353761. The reversal of 81353743 is 34735318.

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 81353743 - 2²¹ = 79256591 is a prime.

It is a super-2 number, since 2×81353743² = 13236863000220098, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81353699 and 81353708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81353243) 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, 2496 + ... + 12997.

It is an arithmetic number, because the mean of its divisors is an integer number (10458450).

Almost surely, 2^81353743 is an apocalyptic number.

81353743 is a deficient number, since it is larger than the sum of its proper divisors (2313857).

81353743 is a wasteful number, since it uses less digits than its factorization.

81353743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15641.

The product of its digits is 30240, while the sum is 34.

The square root of 81353743 is about 9019.6309791477. The cubic root of 81353743 is about 433.3038152806.

The spelling of 81353743 in words is "eighty-one million, three hundred fifty-three thousand, seven hundred forty-three".