667693440 has 192 divisors, whose sum is σ = 2427375600. Its totient is φ = 168652800.

The previous prime is 667693423. The next prime is 667693441. The reversal of 667693440 is 44396766.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667693441) 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, 106390 + ... + 112490.

Almost surely, 2^667693440 is an apocalyptic number.

667693440 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 667693440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1213687800).

667693440 is an abundant number, since it is smaller than the sum of its proper divisors (1759682160).

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

667693440 is a wasteful number, since it uses less digits than its factorization.

667693440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6145 (or 6130 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 45.

The square root of 667693440 is about 25839.7647048111. The cubic root of 667693440 is about 874.0287192500.

The spelling of 667693440 in words is "six hundred sixty-seven million, six hundred ninety-three thousand, four hundred forty".