81651935 has 16 divisors (see below), whose sum is σ = 104784192. Its totient is φ = 60864000.

The previous prime is 81651841. The next prime is 81651943. The reversal of 81651935 is 53915618.

It is not a de Polignac number, because 81651935 - 2¹⁰ = 81650911 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3830 + ... + 13340.

It is an arithmetic number, because the mean of its divisors is an integer number (6549012).

Almost surely, 2^81651935 is an apocalyptic number.

81651935 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

81651935 is a deficient number, since it is larger than the sum of its proper divisors (23132257).

81651935 is a wasteful number, since it uses less digits than its factorization.

81651935 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9634.

The product of its digits is 32400, while the sum is 38.

The square root of 81651935 is about 9036.1460258232. The cubic root of 81651935 is about 433.8325768031.

The spelling of 81651935 in words is "eighty-one million, six hundred fifty-one thousand, nine hundred thirty-five".