1966404864 has 72 divisors (see below), whose sum is σ = 5322330720. Its totient is φ = 644343808.

The previous prime is 1966404863. The next prime is 1966404883. The reversal of 1966404864 is 4684046691.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1966404863) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23614 + ... + 67010.

It is an arithmetic number, because the mean of its divisors is an integer number (73921260).

Almost surely, 2^1966404864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1966404864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2661165360).

1966404864 is an abundant number, since it is smaller than the sum of its proper divisors (3355925856).

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

1966404864 is an equidigital number, since it uses as much as digits as its factorization.

1966404864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43475 (or 43461 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 48.

The square root of 1966404864 is about 44344.1638099085. The cubic root of 1966404864 is about 1252.8266409162.

The spelling of 1966404864 in words is "one billion, nine hundred sixty-six million, four hundred four thousand, eight hundred sixty-four".