8451818640 has 300 divisors, whose sum is σ = 30989276604. Its totient is φ = 2134605312.

The previous prime is 8451818633. The next prime is 8451818657. The reversal of 8451818640 is 468181548.

8451818640 is a `hidden beast` number, since 8 + 451 + 81 + 86 + 40 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 905769216 + 7546049424 = 30096^2 + 86868^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 2337474 + ... + 2341086.

Almost surely, 2^8451818640 is an apocalyptic number.

8451818640 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 8451818640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15494638302).

8451818640 is an abundant number, since it is smaller than the sum of its proper divisors (22537457964).

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

8451818640 is a wasteful number, since it uses less digits than its factorization.

8451818640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3676 (or 3642 counting only the distinct ones).

The product of its (nonzero) digits is 245760, while the sum is 45.

The square root of 8451818640 is about 91933.7731195669. The cubic root of 8451818640 is about 2036.9641695846.

The spelling of 8451818640 in words is "eight billion, four hundred fifty-one million, eight hundred eighteen thousand, six hundred forty".