861840672 has 192 divisors, whose sum is σ = 2912329728. Its totient is φ = 216576000.

The previous prime is 861840599. The next prime is 861840677. The reversal of 861840672 is 276048168.

It is a super-3 number, since 3×861840672³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (861840677) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 227272 + ... + 231032.

It is an arithmetic number, because the mean of its divisors is an integer number (15168384).

Almost surely, 2^861840672 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861840672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1456164864).

861840672 is an abundant number, since it is smaller than the sum of its proper divisors (2050489056).

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

861840672 is a wasteful number, since it uses less digits than its factorization.

861840672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3823 (or 3815 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 42.

The square root of 861840672 is about 29357.1230198056. The cubic root of 861840672 is about 951.6465156591.

The spelling of 861840672 in words is "eight hundred sixty-one million, eight hundred forty thousand, six hundred seventy-two".