81124580 has 12 divisors (see below), whose sum is σ = 170361660. Its totient is φ = 32449824.

The previous prime is 81124577. The next prime is 81124583. The reversal of 81124580 is 8542118.

It is an interprime number because it is at equal distance from previous prime (81124577) and next prime (81124583).

It can be written as a sum of positive squares in 2 ways, for example, as 60621796 + 20502784 = 7786^2 + 4528^2 .

It is not an unprimeable number, because it can be changed into a prime (81124583) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2028095 + ... + 2028134.

It is an arithmetic number, because the mean of its divisors is an integer number (14196805).

Almost surely, 2^81124580 is an apocalyptic number.

It is an amenable number.

81124580 is an abundant number, since it is smaller than the sum of its proper divisors (89237080).

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

81124580 is a wasteful number, since it uses less digits than its factorization.

81124580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4056238 (or 4056236 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 29.

The square root of 81124580 is about 9006.9184519457. The cubic root of 81124580 is about 432.8965790120.

Adding to 81124580 its reverse (8542118), we get a palindrome (89666698).

The spelling of 81124580 in words is "eighty-one million, one hundred twenty-four thousand, five hundred eighty".