81764632 has 32 divisors (see below), whose sum is σ = 161280000. Its totient is φ = 38785824.

The previous prime is 81764623. The next prime is 81764633. The reversal of 81764632 is 23646718.

It is a junction number, because it is equal to n+sod(n) for n = 81764591 and 81764600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81764633) 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 7 ways as a sum of consecutive naturals, for example, 21619 + ... + 25117.

It is an arithmetic number, because the mean of its divisors is an integer number (5040000).

Almost surely, 2^81764632 is an apocalyptic number.

It is an amenable number.

81764632 is a deficient number, since it is larger than the sum of its proper divisors (79515368).

81764632 is a wasteful number, since it uses less digits than its factorization.

81764632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3655 (or 3651 counting only the distinct ones).

The product of its digits is 48384, while the sum is 37.

The square root of 81764632 is about 9042.3797752583. The cubic root of 81764632 is about 434.0320787235.

The spelling of 81764632 in words is "eighty-one million, seven hundred sixty-four thousand, six hundred thirty-two".