3987394840 has 256 divisors, whose sum is σ = 11031552000. Its totient is φ = 1277337600.

The previous prime is 3987394823. The next prime is 3987394843. The reversal of 3987394840 is 484937893.

3987394840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×3987394840² = 31798635220117251200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (55).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3987394843) 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, 20037061 + ... + 20037259.

It is an arithmetic number, because the mean of its divisors is an integer number (43092000).

Almost surely, 2^3987394840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3987394840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5515776000).

3987394840 is an abundant number, since it is smaller than the sum of its proper divisors (7044157160).

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

3987394840 is a wasteful number, since it uses less digits than its factorization.

3987394840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 378 (or 374 counting only the distinct ones).

The product of its (nonzero) digits is 5225472, while the sum is 55.

The square root of 3987394840 is about 63145.8220312318. The cubic root of 3987394840 is about 1585.7318436649.

The spelling of 3987394840 in words is "three billion, nine hundred eighty-seven million, three hundred ninety-four thousand, eight hundred forty".