81628942 has 16 divisors (see below), whose sum is σ = 126277632. Its totient is φ = 39553560.

The previous prime is 81628891. The next prime is 81628949. The reversal of 81628942 is 24982618.

It is a junction number, because it is equal to n+sod(n) for n = 81628895 and 81628904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81628949) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5467 + ... + 13897.

It is an arithmetic number, because the mean of its divisors is an integer number (7892352).

Almost surely, 2^81628942 is an apocalyptic number.

81628942 is a deficient number, since it is larger than the sum of its proper divisors (44648690).

81628942 is a wasteful number, since it uses less digits than its factorization.

81628942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8583.

The product of its digits is 55296, while the sum is 40.

The square root of 81628942 is about 9034.8736571133. The cubic root of 81628942 is about 433.7918508896.

The spelling of 81628942 in words is "eighty-one million, six hundred twenty-eight thousand, nine hundred forty-two".