667766400 has 384 divisors, whose sum is σ = 2651020800. Its totient is φ = 144322560.

The previous prime is 667766399. The next prime is 667766401. The reversal of 667766400 is 4667766.

It is an interprime number because it is at equal distance from previous prime (667766399) and next prime (667766401).

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (667766401) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1276539 + ... + 1277061.

It is an arithmetic number, because the mean of its divisors is an integer number (6903700).

Almost surely, 2^667766400 is an apocalyptic number.

667766400 is a gapful number since it is divisible by the number (60) 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 667766400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1325510400).

667766400 is an abundant number, since it is smaller than the sum of its proper divisors (1983254400).

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

667766400 is a wasteful number, since it uses less digits than its factorization.

667766400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 576 (or 559 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 42.

The square root of 667766400 is about 25841.1764438077. The cubic root of 667766400 is about 874.0605536263.

The spelling of 667766400 in words is "six hundred sixty-seven million, seven hundred sixty-six thousand, four hundred".