1818319640 has 16 divisors (see below), whose sum is σ = 4091219280. Its totient is φ = 727327840.

The previous prime is 1818319571. The next prime is 1818319649. The reversal of 1818319640 is 469138181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1818319649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22728956 + ... + 22729035.

It is an arithmetic number, because the mean of its divisors is an integer number (255701205).

Almost surely, 2^1818319640 is an apocalyptic number.

1818319640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1818319640 is an abundant number, since it is smaller than the sum of its proper divisors (2272899640).

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

1818319640 is a wasteful number, since it uses less digits than its factorization.

1818319640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45458002 (or 45457998 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 1818319640 is about 42641.7593445674. The cubic root of 1818319640 is about 1220.5532830385.

The spelling of 1818319640 in words is "one billion, eight hundred eighteen million, three hundred nineteen thousand, six hundred forty".