4021778 has 8 divisors (see below), whose sum is σ = 6240780. Its totient is φ = 1941520.

The previous prime is 4021777. The next prime is 4021867. The reversal of 4021778 is 8771204.

It can be written as a sum of positive squares in 2 ways, for example, as 3972049 + 49729 = 1993^2 + 223^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (29).

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 4021778.

It is not an unprimeable number, because it can be changed into a prime (4021777) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34613 + ... + 34728.

Almost surely, 2^4021778 is an apocalyptic number.

4021778 is a deficient number, since it is larger than the sum of its proper divisors (2219002).

4021778 is a wasteful number, since it uses less digits than its factorization.

4021778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69372.

The product of its (nonzero) digits is 3136, while the sum is 29.

The square root of 4021778 is about 2005.4371094602. The cubic root of 4021778 is about 159.0276707772.

The spelling of 4021778 in words is "four million, twenty-one thousand, seven hundred seventy-eight".