81742100 has 36 divisors (see below), whose sum is σ = 193508448. Its totient is φ = 29724000.

The previous prime is 81742099. The next prime is 81742109. The reversal of 81742100 is 124718.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81742109) 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 11 ways as a sum of consecutive naturals, for example, 36056 + ... + 38255.

Almost surely, 2^81742100 is an apocalyptic number.

It is an amenable number.

81742100 is an abundant number, since it is smaller than the sum of its proper divisors (111766348).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81742100 is a wasteful number, since it uses less digits than its factorization.

81742100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74336 (or 74329 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 81742100 is about 9041.1337784594. The cubic root of 81742100 is about 433.9922061078.

Adding to 81742100 its reverse (124718), we get a palindrome (81866818).

The spelling of 81742100 in words is "eighty-one million, seven hundred forty-two thousand, one hundred".