81451748 has 24 divisors (see below), whose sum is σ = 166879104. Its totient is φ = 34056000.

The previous prime is 81451729. The next prime is 81451751. The reversal of 81451748 is 84715418.

It is a happy number.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34328 + ... + 36623.

It is an arithmetic number, because the mean of its divisors is an integer number (6953296).

Almost surely, 2^81451748 is an apocalyptic number.

It is an amenable number.

81451748 is an abundant number, since it is smaller than the sum of its proper divisors (85427356).

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

81451748 is a wasteful number, since it uses less digits than its factorization.

81451748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71003 (or 71001 counting only the distinct ones).

The product of its digits is 35840, while the sum is 38.

The square root of 81451748 is about 9025.0622158520. The cubic root of 81451748 is about 433.4777425340.

The spelling of 81451748 in words is "eighty-one million, four hundred fifty-one thousand, seven hundred forty-eight".