1999969920 has 512 divisors, whose sum is σ = 7916832000. Its totient is φ = 473776128.

The previous prime is 1999969919. The next prime is 1999969921. The reversal of 1999969920 is 299699991.

It is an interprime number because it is at equal distance from previous prime (1999969919) and next prime (1999969921).

It is not an unprimeable number, because it can be changed into a prime (1999969921) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6514407 + ... + 6514713.

Almost surely, 2^1999969920 is an apocalyptic number.

1999969920 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 1999969920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3958416000).

1999969920 is an abundant number, since it is smaller than the sum of its proper divisors (5916862080).

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

1999969920 is a wasteful number, since it uses less digits than its factorization.

1999969920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 377 (or 359 counting only the distinct ones).

The product of its (nonzero) digits is 6377292, while the sum is 63.

The square root of 1999969920 is about 44721.0232441075. The cubic root of 1999969920 is about 1259.9147334590.

The spelling of 1999969920 in words is "one billion, nine hundred ninety-nine million, nine hundred sixty-nine thousand, nine hundred twenty".