3978618 has 32 divisors (see below), whose sum is σ = 9309696. Its totient is φ = 1109808.

The previous prime is 3978593. The next prime is 3978641. The reversal of 3978618 is 8168793.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 3978618.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 705 + ... + 2907.

It is an arithmetic number, because the mean of its divisors is an integer number (290928).

Almost surely, 2^3978618 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3978618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4654848).

3978618 is an abundant number, since it is smaller than the sum of its proper divisors (5331078).

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

3978618 is a wasteful number, since it uses less digits than its factorization.

3978618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2258.

The product of its digits is 72576, while the sum is 42.

The square root of 3978618 is about 1994.6473372504. The cubic root of 3978618 is about 158.4567512953.

The spelling of 3978618 in words is "three million, nine hundred seventy-eight thousand, six hundred eighteen".