6861664290 has 192 divisors, whose sum is σ = 18818634240. Its totient is φ = 1591349760.

The previous prime is 6861664261. The next prime is 6861664297. The reversal of 6861664290 is 924661686.

It is a happy number.

It is a super-2 number, since 2×6861664290² = 94164873657322408200, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6861664297) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 16298280 + ... + 16298700.

It is an arithmetic number, because the mean of its divisors is an integer number (98013720).

Almost surely, 2^6861664290 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6861664290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9409317120).

6861664290 is an abundant number, since it is smaller than the sum of its proper divisors (11956969950).

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

6861664290 is a wasteful number, since it uses less digits than its factorization.

6861664290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 569 (or 546 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 48.

The square root of 6861664290 is about 82835.1633667732. The cubic root of 6861664290 is about 1900.2459783107.

The spelling of 6861664290 in words is "six billion, eight hundred sixty-one million, six hundred sixty-four thousand, two hundred ninety".