997861144900 has 81 divisors (see below), whose sum is σ = 2180925010173. Its totient is φ = 396295509600.

The previous prime is 997861144897. The next prime is 997861144909. The reversal of 997861144900 is 9441168799.

The square root of 997861144900 is 998930.

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

It can be written as a sum of positive squares in only one way, i.e., 359230012164 + 638631132736 = 599358^2 + 799144^2 .

It is a super-2 number, since 2×997861144900² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (997861144909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1907956039 + ... + 1907956561.

Almost surely, 2^997861144900 is an apocalyptic number.

997861144900 is the 998930-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 997861144900

997861144900 is an abundant number, since it is smaller than the sum of its proper divisors (1183063865273).

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

997861144900 is an equidigital number, since it uses as much as digits as its factorization.

997861144900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1442 (or 721 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 58.

It can be divided in two parts, 997861 and 144900, that added together give a square (1142761 = 1069²).

The spelling of 997861144900 in words is "nine hundred ninety-seven billion, eight hundred sixty-one million, one hundred forty-four thousand, nine hundred".