81634127 has 4 divisors (see below), whose sum is σ = 85930680. Its totient is φ = 77337576.

The previous prime is 81634121. The next prime is 81634139. The reversal of 81634127 is 72143618.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81634127 - 2²² = 77439823 is a prime.

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

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81634093 and 81634102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81634121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2148248 + ... + 2148285.

It is an arithmetic number, because the mean of its divisors is an integer number (21482670).

Almost surely, 2^81634127 is an apocalyptic number.

81634127 is a deficient number, since it is larger than the sum of its proper divisors (4296553).

81634127 is a wasteful number, since it uses less digits than its factorization.

81634127 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4296552.

The product of its digits is 8064, while the sum is 32.

The square root of 81634127 is about 9035.1605962484. The cubic root of 81634127 is about 433.8010353899.

It can be divided in two parts, 816 and 34127, that added together give a palindrome (34943).

The spelling of 81634127 in words is "eighty-one million, six hundred thirty-four thousand, one hundred twenty-seven".