81530410 has 32 divisors (see below), whose sum is σ = 158597712. Its totient is φ = 29998080.

The previous prime is 81530381. The next prime is 81530413. The reversal of 81530410 is 1403518.

It can be written as a sum of positive squares in 8 ways, for example, as 43681 + 81486729 = 209^2 + 9027^2 .

It is not an unprimeable number, because it can be changed into a prime (81530413) 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, 42880 + ... + 44740.

Almost surely, 2^81530410 is an apocalyptic number.

81530410 is a deficient number, since it is larger than the sum of its proper divisors (77067302).

81530410 is a wasteful number, since it uses less digits than its factorization.

81530410 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2218.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 81530410 is about 9029.4191396789. The cubic root of 81530410 is about 433.6172413012.

Adding to 81530410 its reverse (1403518), we get a palindrome (82933928).

The spelling of 81530410 in words is "eighty-one million, five hundred thirty thousand, four hundred ten".