1978800 has 120 divisors (see below), whose sum is σ = 6780816. Its totient is φ = 491520.

The previous prime is 1978799. The next prime is 1978807. The reversal of 1978800 is 88791.

1978800 = 233² + 234² + ... + 264².

It is a tau number, because it is divible by the number of its divisors (120).

It is not an unprimeable number, because it can be changed into a prime (1978807) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20352 + ... + 20448.

2^1978800 is an apocalyptic number.

1978800 is a gapful number since it is divisible by the number (10) 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 1978800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3390408).

1978800 is an abundant number, since it is smaller than the sum of its proper divisors (4802016).

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

1978800 is a wasteful number, since it uses less digits than its factorization.

1978800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 33.

The square root of 1978800 is about 1406.6982618885. The cubic root of 1978800 is about 125.5453506149.

The spelling of 1978800 in words is "one million, nine hundred seventy-eight thousand, eight hundred".