3899920 has 60 divisors (see below), whose sum is σ = 9614340. Its totient is φ = 1469440.

The previous prime is 3899887. The next prime is 3899927. The reversal of 3899920 is 299983.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 1327104 + 2572816 = 1152^2 + 1604^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3899927) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 95100 + ... + 95140.

It is an arithmetic number, because the mean of its divisors is an integer number (160239).

Almost surely, 2^3899920 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 3899920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4807170).

3899920 is an abundant number, since it is smaller than the sum of its proper divisors (5714420).

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

3899920 is a wasteful number, since it uses less digits than its factorization.

3899920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 40.

The square root of 3899920 is about 1974.8215109219. The cubic root of 3899920 is about 157.4050153748.

The spelling of 3899920 in words is "three million, eight hundred ninety-nine thousand, nine hundred twenty".