81356152900 has 81 divisors (see below), whose sum is σ = 194126099223. Its totient is φ = 29572646400.

The previous prime is 81356152811. The next prime is 81356152931. The reversal of 81356152900 is 925165318.

The square root of 81356152900 is 285230.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 112911876 + 81243241024 = 10626^2 + 285032^2 .

It is a super-2 number, since 2×81356152900² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 31374004 + ... + 31376596.

Almost surely, 2^81356152900 is an apocalyptic number.

81356152900 is the 285230-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81356152900

81356152900 is an abundant number, since it is smaller than the sum of its proper divisors (112769946323).

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

81356152900 is a wasteful number, since it uses less digits than its factorization.

81356152900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5222 (or 2611 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 40.

It can be divided in two parts, 81356 and 152900, that added together give a 4-th power (234256 = 22⁴).

The spelling of 81356152900 in words is "eighty-one billion, three hundred fifty-six million, one hundred fifty-two thousand, nine hundred".