1986487920 has 240 divisors, whose sum is σ = 7019550720. Its totient is φ = 502470144.

The previous prime is 1986487901. The next prime is 1986487939. The reversal of 1986487920 is 297846891.

It is an interprime number because it is at equal distance from previous prime (1986487901) and next prime (1986487939).

It is a tau number, because it is divible by the number of its divisors (240).

It is a super-2 number, since 2×1986487920² = 7892268512611852800, which contains 22 as substring.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2301409 + ... + 2302271.

It is an arithmetic number, because the mean of its divisors is an integer number (29248128).

Almost surely, 2^1986487920 is an apocalyptic number.

1986487920 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 1986487920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3509775360).

1986487920 is an abundant number, since it is smaller than the sum of its proper divisors (5033062800).

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

1986487920 is a wasteful number, since it uses less digits than its factorization.

1986487920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1044 (or 1035 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The square root of 1986487920 is about 44570.0338792781. The cubic root of 1986487920 is about 1257.0772770296.

The spelling of 1986487920 in words is "one billion, nine hundred eighty-six million, four hundred eighty-seven thousand, nine hundred twenty".