861299818608 has 40 divisors (see below), whose sum is σ = 2236205584000. Its totient is φ = 285657223104.

The previous prime is 861299818607. The next prime is 861299818651. The reversal of 861299818608 is 806818992168.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861299818607) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45075238 + ... + 45094341.

It is an arithmetic number, because the mean of its divisors is an integer number (55905139600).

Almost surely, 2^861299818608 is an apocalyptic number.

It is an amenable number.

861299818608 is an abundant number, since it is smaller than the sum of its proper divisors (1374905765392).

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

861299818608 is a wasteful number, since it uses less digits than its factorization.

861299818608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90169789 (or 90169783 counting only the distinct ones).

The product of its (nonzero) digits is 23887872, while the sum is 66.

The spelling of 861299818608 in words is "eight hundred sixty-one billion, two hundred ninety-nine million, eight hundred eighteen thousand, six hundred eight".