81725345 has 8 divisors (see below), whose sum is σ = 105614376. Its totient is φ = 60350976.

The previous prime is 81725323. The next prime is 81725351. The reversal of 81725345 is 54352718.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4443664 + 77281681 = 2108^2 + 8791^2 .

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 81725345 - 2¹⁴ = 81708961 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 628592 + ... + 628721.

It is an arithmetic number, because the mean of its divisors is an integer number (13201797).

Almost surely, 2^81725345 is an apocalyptic number.

It is an amenable number.

81725345 is a deficient number, since it is larger than the sum of its proper divisors (23889031).

81725345 is a wasteful number, since it uses less digits than its factorization.

81725345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1257331.

The product of its digits is 33600, while the sum is 35.

The square root of 81725345 is about 9040.2071325827. The cubic root of 81725345 is about 433.9625517180.

It can be divided in two parts, 817 and 25345, that added together give a palindrome (26162).

The spelling of 81725345 in words is "eighty-one million, seven hundred twenty-five thousand, three hundred forty-five".