861997119844 has 243 divisors, whose sum is σ = 1927802306073. Its totient is φ = 336198541056.

The previous prime is 861997119839. The next prime is 861997119857. The reversal of 861997119844 is 448911799168.

The square root of 861997119844 is 928438.

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., 671105024100 + 190892095744 = 819210^2 + 436912^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 861997119844.

It is an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 10385507427 + ... + 10385507509.

Almost surely, 2^861997119844 is an apocalyptic number.

861997119844 is the 928438-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861997119844

861997119844 is an abundant number, since it is smaller than the sum of its proper divisors (1065805186229).

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

861997119844 is a wasteful number, since it uses less digits than its factorization.

861997119844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 312 (or 156 counting only the distinct ones).

The product of its digits is 31352832, while the sum is 67.

The spelling of 861997119844 in words is "eight hundred sixty-one billion, nine hundred ninety-seven million, one hundred nineteen thousand, eight hundred forty-four".