3906440 has 32 divisors (see below), whose sum is σ = 8939160. Its totient is φ = 1536000.

The previous prime is 3906437. The next prime is 3906467. The reversal of 3906440 is 446093.

It can be written as a sum of positive squares in 4 ways, for example, as 3319684 + 586756 = 1822^2 + 766^2 .

It is a Smith number, since the sum of its digits (26) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1640 + ... + 3240.

Almost surely, 2^3906440 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 3906440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4469580).

3906440 is an abundant number, since it is smaller than the sum of its proper divisors (5032720).

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

3906440 is a wasteful number, since it uses less digits than its factorization.

3906440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1673 (or 1669 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 3906440 is about 1976.4716036412. The cubic root of 3906440 is about 157.4926846355.

The spelling of 3906440 in words is "three million, nine hundred six thousand, four hundred forty".