1916978400 has 504 divisors, whose sum is σ = 7428508920. Its totient is φ = 481489920.

The previous prime is 1916978383. The next prime is 1916978431. The reversal of 1916978400 is 48796191.

It is a happy number.

1916978400 is a `hidden beast` number, since 19 + 169 + 78 + 400 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 11080714 + ... + 11080886.

It is an arithmetic number, because the mean of its divisors is an integer number (14739105).

Almost surely, 2^1916978400 is an apocalyptic number.

1916978400 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 1916978400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3714254460).

1916978400 is an abundant number, since it is smaller than the sum of its proper divisors (5511530520).

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

1916978400 is a wasteful number, since it uses less digits than its factorization.

1916978400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230 (or 202 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The square root of 1916978400 is about 43783.3118893489. The cubic root of 1916978400 is about 1242.2406590992.

The spelling of 1916978400 in words is "one billion, nine hundred sixteen million, nine hundred seventy-eight thousand, four hundred".