861953760 has 144 divisors (see below), whose sum is σ = 3036458880. Its totient is φ = 222428160.

The previous prime is 861953723. The next prime is 861953767. The reversal of 861953760 is 67359168.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861953767) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34986 + ... + 54294.

It is an arithmetic number, because the mean of its divisors is an integer number (21086520).

Almost surely, 2^861953760 is an apocalyptic number.

861953760 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861953760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1518229440).

861953760 is an abundant number, since it is smaller than the sum of its proper divisors (2174505120).

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

861953760 is a wasteful number, since it uses less digits than its factorization.

861953760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19361 (or 19350 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 861953760 is about 29359.0490309206. The cubic root of 861953760 is about 951.6881378513.

The spelling of 861953760 in words is "eight hundred sixty-one million, nine hundred fifty-three thousand, seven hundred sixty".