1999854540 has 144 divisors (see below), whose sum is σ = 6278047776. Its totient is φ = 514944000.

The previous prime is 1999854533. The next prime is 1999854541. The reversal of 1999854540 is 454589991.

1999854540 is a `hidden beast` number, since 1 + 9 + 9 + 98 + 5 + 4 + 540 = 666.

It is a super-2 number, since 2×1999854540² = 7998836362317223200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1999854541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 744039 + ... + 746721.

It is an arithmetic number, because the mean of its divisors is an integer number (43597554).

Almost surely, 2^1999854540 is an apocalyptic number.

1999854540 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 1999854540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3139023888).

1999854540 is an abundant number, since it is smaller than the sum of its proper divisors (4278193236).

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

1999854540 is a wasteful number, since it uses less digits than its factorization.

1999854540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2840 (or 2835 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 54.

The square root of 1999854540 is about 44719.7332281846. The cubic root of 1999854540 is about 1259.8905044684.

The spelling of 1999854540 in words is "one billion, nine hundred ninety-nine million, eight hundred fifty-four thousand, five hundred forty".