1999766340 has 768 divisors, whose sum is σ = 8128512000. Its totient is φ = 400619520.

The previous prime is 1999766309. The next prime is 1999766347. The reversal of 1999766340 is 436679991.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (1999766347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 42548197 + ... + 42548243.

It is an arithmetic number, because the mean of its divisors is an integer number (10584000).

Almost surely, 2^1999766340 is an apocalyptic number.

1999766340 is a gapful number since it is divisible by the number (10) 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 1999766340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4064256000).

1999766340 is an abundant number, since it is smaller than the sum of its proper divisors (6128745660).

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

1999766340 is a wasteful number, since it uses less digits than its factorization.

1999766340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137 (or 129 counting only the distinct ones).

The product of its (nonzero) digits is 2204496, while the sum is 54.

The square root of 1999766340 is about 44718.7470754716. The cubic root of 1999766340 is about 1259.8719824586.

The spelling of 1999766340 in words is "one billion, nine hundred ninety-nine million, seven hundred sixty-six thousand, three hundred forty".