1999705920 has 224 divisors, whose sum is σ = 7077456000. Its totient is φ = 475398144.

The previous prime is 1999705891. The next prime is 1999705943. The reversal of 1999705920 is 295079991.

It is a hoax number, since the sum of its digits (51) 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 (51).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 306856 + ... + 313304.

Almost surely, 2^1999705920 is an apocalyptic number.

1999705920 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 1999705920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3538728000).

1999705920 is an abundant number, since it is smaller than the sum of its proper divisors (5077750080).

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

1999705920 is a wasteful number, since it uses less digits than its factorization.

1999705920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6505 (or 6495 counting only the distinct ones).

The product of its (nonzero) digits is 459270, while the sum is 51.

The square root of 1999705920 is about 44718.0715147691. The cubic root of 1999705920 is about 1259.8592939375.

The spelling of 1999705920 in words is "one billion, nine hundred ninety-nine million, seven hundred five thousand, nine hundred twenty".