861630000 has 400 divisors, whose sum is σ = 3477086976. Its totient is φ = 178560000.

The previous prime is 861629981. The next prime is 861630013. The reversal of 861630000 is 36168.

It is a tau number, because it is divible by the number of its divisors (400).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2309814 + ... + 2310186.

Almost surely, 2^861630000 is an apocalyptic number.

861630000 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 861630000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1738543488).

861630000 is an abundant number, since it is smaller than the sum of its proper divisors (2615456976).

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

861630000 is a wasteful number, since it uses less digits than its factorization.

861630000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 422 (or 401 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 861630000 is about 29353.5347104910. The cubic root of 861630000 is about 951.5689678325.

Adding to 861630000 its reverse (36168), we get a palindrome (861666168).

The spelling of 861630000 in words is "eight hundred sixty-one million, six hundred thirty thousand".