1964390400 has 864 divisors, whose sum is σ = 8683038000. Its totient is φ = 433520640.

The previous prime is 1964390387. The next prime is 1964390419. The reversal of 1964390400 is 40934691.

1964390400 is a `hidden beast` number, since 1 + 9 + 643 + 9 + 0 + 4 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

It is a super-2 number, since 2×1964390400² = 7717659287224320000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 67737586 + ... + 67737614.

Almost surely, 2^1964390400 is an apocalyptic number.

1964390400 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 1964390400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4341519000).

1964390400 is an abundant number, since it is smaller than the sum of its proper divisors (6718647600).

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

1964390400 is a wasteful number, since it uses less digits than its factorization.

1964390400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 1964390400 is about 44321.4440197970. Note that the first 3 decimals coincide. The cubic root of 1964390400 is about 1252.3986794586.

The spelling of 1964390400 in words is "one billion, nine hundred sixty-four million, three hundred ninety thousand, four hundred".