81543325 has 6 divisors (see below), whose sum is σ = 101113754. Its totient is φ = 65234640.

The previous prime is 81543317. The next prime is 81543367. The reversal of 81543325 is 52334518.

It can be written as a sum of positive squares in 3 ways, for example, as 6859161 + 74684164 = 2619^2 + 8642^2 .

It is not a de Polignac number, because 81543325 - 2³ = 81543317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1630842 + ... + 1630891.

Almost surely, 2^81543325 is an apocalyptic number.

It is an amenable number.

81543325 is a deficient number, since it is larger than the sum of its proper divisors (19570429).

81543325 is a wasteful number, since it uses less digits than its factorization.

81543325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3261743 (or 3261738 counting only the distinct ones).

The product of its digits is 14400, while the sum is 31.

The square root of 81543325 is about 9030.1342736418. The cubic root of 81543325 is about 433.6401361163.

The spelling of 81543325 in words is "eighty-one million, five hundred forty-three thousand, three hundred twenty-five".