1999134720 has 672 divisors, whose sum is σ = 8280623520. Its totient is φ = 440401920.

The previous prime is 1999134667. The next prime is 1999134757. The reversal of 1999134720 is 274319991.

1999134720 is a `hidden beast` number, since 1 + 99 + 91 + 3 + 472 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 68935666 + ... + 68935694.

Almost surely, 2^1999134720 is an apocalyptic number.

1999134720 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 1999134720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4140311760).

1999134720 is an abundant number, since it is smaller than the sum of its proper divisors (6281488800).

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

1999134720 is a wasteful number, since it uses less digits than its factorization.

1999134720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94 (or 67 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The square root of 1999134720 is about 44711.6843789182. The cubic root of 1999134720 is about 1259.7393262710.

The spelling of 1999134720 in words is "one billion, nine hundred ninety-nine million, one hundred thirty-four thousand, seven hundred twenty".