81634064 has 10 divisors (see below), whose sum is σ = 158166030. Its totient is φ = 40817024.

The previous prime is 81634057. The next prime is 81634121. The reversal of 81634064 is 46043618.

It can be written as a sum of positive squares in only one way, i.e., 81144064 + 490000 = 9008^2 + 700^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81634064.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2551049 + ... + 2551080.

It is an arithmetic number, because the mean of its divisors is an integer number (15816603).

Almost surely, 2^81634064 is an apocalyptic number.

It is an amenable number.

81634064 is a deficient number, since it is larger than the sum of its proper divisors (76531966).

81634064 is a wasteful number, since it uses less digits than its factorization.

81634064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5102137 (or 5102131 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 32.

The square root of 81634064 is about 9035.1571098681. The cubic root of 81634064 is about 433.8009237966.

The spelling of 81634064 in words is "eighty-one million, six hundred thirty-four thousand, sixty-four".