861146640 has 100 divisors (see below), whose sum is σ = 2990912364. Its totient is φ = 229637376.

The previous prime is 861146609. The next prime is 861146647. The reversal of 861146640 is 46641168.

861146640 is a `hidden beast` number, since 8 + 6 + 1 + 1 + 4 + 6 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 601034256 + 260112384 = 24516^2 + 16128^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 861146595 and 861146604.

It is not an unprimeable number, because it can be changed into a prime (861146647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 59967 + ... + 72926.

Almost surely, 2^861146640 is an apocalyptic number.

861146640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

861146640 is an abundant number, since it is smaller than the sum of its proper divisors (2129765724).

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

861146640 is a wasteful number, since it uses less digits than its factorization.

861146640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132918 (or 132903 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 861146640 is about 29345.3001347746. The cubic root of 861146640 is about 951.3909964638.

The spelling of 861146640 in words is "eight hundred sixty-one million, one hundred forty-six thousand, six hundred forty".