81434529 has 12 divisors (see below), whose sum is σ = 128321232. Its totient is φ = 49354200.

The previous prime is 81434527. The next prime is 81434599. The reversal of 81434529 is 92543418.

It is not a de Polignac number, because 81434529 - 2¹ = 81434527 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 81434493 and 81434502.

It is not an unprimeable number, because it can be changed into a prime (81434527) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 411187 + ... + 411384.

It is an arithmetic number, because the mean of its divisors is an integer number (10693436).

Almost surely, 2^81434529 is an apocalyptic number.

It is an amenable number.

81434529 is a deficient number, since it is larger than the sum of its proper divisors (46886703).

81434529 is a wasteful number, since it uses less digits than its factorization.

81434529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 822588 (or 822585 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 81434529 is about 9024.1082107874. The cubic root of 81434529 is about 433.4471944715.

Subtracting 81434529 from its reverse (92543418), we obtain a square (11108889 = 3333²).

The spelling of 81434529 in words is "eighty-one million, four hundred thirty-four thousand, five hundred twenty-nine".