81604748 has 12 divisors (see below), whose sum is σ = 143314920. Its totient is φ = 40657632.

The previous prime is 81604673. The next prime is 81604793. The reversal of 81604748 is 84740618.

It is a super-2 number, since 2×81604748² = 13318669792287008, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34913 + ... + 37176.

It is an arithmetic number, because the mean of its divisors is an integer number (11942910).

Almost surely, 2^81604748 is an apocalyptic number.

It is an amenable number.

81604748 is a deficient number, since it is larger than the sum of its proper divisors (61710172).

81604748 is a wasteful number, since it uses less digits than its factorization.

81604748 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72376 (or 72374 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 38.

The square root of 81604748 is about 9033.5346349034. The cubic root of 81604748 is about 433.7489894696.

The spelling of 81604748 in words is "eighty-one million, six hundred four thousand, seven hundred forty-eight".