81630044 has 6 divisors (see below), whose sum is σ = 142852584. Its totient is φ = 40815020.

The previous prime is 81630019. The next prime is 81630067. The reversal of 81630044 is 44003618.

It is a junction number, because it is equal to n+sod(n) for n = 81629995 and 81630022.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10203752 + ... + 10203759.

It is an arithmetic number, because the mean of its divisors is an integer number (23808764).

Almost surely, 2^81630044 is an apocalyptic number.

It is an amenable number.

81630044 is a deficient number, since it is larger than the sum of its proper divisors (61222540).

81630044 is a wasteful number, since it uses less digits than its factorization.

81630044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20407515 (or 20407513 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 81630044 is about 9034.9346428184. The cubic root of 81630044 is about 433.7938029606.

The spelling of 81630044 in words is "eighty-one million, six hundred thirty thousand, forty-four".