81625630 has 8 divisors (see below), whose sum is σ = 146926152. Its totient is φ = 32650248.

The previous prime is 81625613. The next prime is 81625637. The reversal of 81625630 is 3652618.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 81625592 and 81625601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81625637) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 4081272 + ... + 4081291.

It is an arithmetic number, because the mean of its divisors is an integer number (18365769).

Almost surely, 2^81625630 is an apocalyptic number.

81625630 is a deficient number, since it is larger than the sum of its proper divisors (65300522).

81625630 is a wasteful number, since it uses less digits than its factorization.

81625630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8162570.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 81625630 is about 9034.6903654746. The cubic root of 81625630 is about 433.7859839426.

The spelling of 81625630 in words is "eighty-one million, six hundred twenty-five thousand, six hundred thirty".