81012634 has 4 divisors (see below), whose sum is σ = 121518954. Its totient is φ = 40506316.

The previous prime is 81012629. The next prime is 81012653. The reversal of 81012634 is 43621018.

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

It can be written as a sum of positive squares in only one way, i.e., 77000625 + 4012009 = 8775^2 + 2003^2 .

It is a junction number, because it is equal to n+sod(n) for n = 81012599 and 81012608.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20253157 + ... + 20253160.

Almost surely, 2^81012634 is an apocalyptic number.

81012634 is a deficient number, since it is larger than the sum of its proper divisors (40506320).

81012634 is a wasteful number, since it uses less digits than its factorization.

81012634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40506319.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 81012634 is about 9000.7018615217. The cubic root of 81012634 is about 432.6973654549.

The spelling of 81012634 in words is "eighty-one million, twelve thousand, six hundred thirty-four".