667193640 has 32 divisors (see below), whose sum is σ = 2001581280. Its totient is φ = 177918272.

The previous prime is 667193629. The next prime is 667193641. The reversal of 667193640 is 46391766.

It is a super-4 number, since 4×667193640⁴ (a number of 36 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 667193592 and 667193601.

It is not an unprimeable number, because it can be changed into a prime (667193641) 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, 2779854 + ... + 2780093.

It is an arithmetic number, because the mean of its divisors is an integer number (62549415).

Almost surely, 2^667193640 is an apocalyptic number.

667193640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

667193640 is an abundant number, since it is smaller than the sum of its proper divisors (1334387640).

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

667193640 is a wasteful number, since it uses less digits than its factorization.

667193640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5559961 (or 5559957 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 42.

The square root of 667193640 is about 25830.0917536117. The cubic root of 667193640 is about 873.8105809191.

The spelling of 667193640 in words is "six hundred sixty-seven million, one hundred ninety-three thousand, six hundred forty".