1778868 has 96 divisors (see below), whose sum is σ = 5707520. Its totient is φ = 466560.

The previous prime is 1778857. The next prime is 1778869. The reversal of 1778868 is 8688771.

It is a super-2 number, since 2×1778868² = 6328742722848, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1778869) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9738 + ... + 9918.

2^1778868 is an apocalyptic number.

1778868 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1778868, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2853760).

1778868 is an abundant number, since it is smaller than the sum of its proper divisors (3928652).

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

1778868 is a wasteful number, since it uses less digits than its factorization.

1778868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214 (or 206 counting only the distinct ones).

The product of its digits is 150528, while the sum is 45.

The square root of 1778868 is about 1333.7421040066. The cubic root of 1778868 is about 121.1661311108.

Subtracting 1778868 from its reverse (8688771), we obtain a triangular number (6909903 = T₃₇₁₇).

It can be divided in two parts, 177 and 8868, that added together give a triangular number (9045 = T₁₃₄).

The spelling of 1778868 in words is "one million, seven hundred seventy-eight thousand, eight hundred sixty-eight".