81448810 has 32 divisors (see below), whose sum is σ = 150232320. Its totient is φ = 31781568.

The previous prime is 81448799. The next prime is 81448817. The reversal of 81448810 is 1884418.

It is a happy number.

It is a super-2 number, since 2×81448810² = 13267817300832200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81448817) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 126349 + ... + 126991.

It is an arithmetic number, because the mean of its divisors is an integer number (4694760).

Almost surely, 2^81448810 is an apocalyptic number.

81448810 is a deficient number, since it is larger than the sum of its proper divisors (68783510).

81448810 is a wasteful number, since it uses less digits than its factorization.

81448810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 942.

The product of its (nonzero) digits is 8192, while the sum is 34.

The square root of 81448810 is about 9024.8994454232. The cubic root of 81448810 is about 433.4725305611.

The spelling of 81448810 in words is "eighty-one million, four hundred forty-eight thousand, eight hundred ten".