1993986540 has 576 divisors, whose sum is σ = 8072064000. Its totient is φ = 386684928.

The previous prime is 1993986539. The next prime is 1993986551. The reversal of 1993986540 is 456893991.

1993986540 is a `hidden beast` number, since 1 + 9 + 9 + 3 + 98 + 6 + 540 = 666.

It is an unprimeable number.

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 191 ways as a sum of consecutive naturals, for example, 13382386 + ... + 13382534.

It is an arithmetic number, because the mean of its divisors is an integer number (14014000).

Almost surely, 2^1993986540 is an apocalyptic number.

1993986540 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 1993986540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4036032000).

1993986540 is an abundant number, since it is smaller than the sum of its proper divisors (6078077460).

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

1993986540 is a wasteful number, since it uses less digits than its factorization.

1993986540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246 (or 241 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 54.

The square root of 1993986540 is about 44654.0764096628. The cubic root of 1993986540 is about 1258.6570347236.

The spelling of 1993986540 in words is "one billion, nine hundred ninety-three million, nine hundred eighty-six thousand, five hundred forty".