667401840 has 120 divisors (see below), whose sum is σ = 2561571168. Its totient is φ = 152547840.

The previous prime is 667401829. The next prime is 667401857. The reversal of 667401840 is 48104766.

It is a tau number, because it is divible by the number of its divisors (120).

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

It is a junction number, because it is equal to n+sod(n) for n = 667401795 and 667401804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61171 + ... + 71250.

Almost surely, 2^667401840 is an apocalyptic number.

667401840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

667401840 is an abundant number, since it is smaller than the sum of its proper divisors (1894169328).

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

667401840 is a wasteful number, since it uses less digits than its factorization.

667401840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132447 (or 132438 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 667401840 is about 25834.1216223815. The cubic root of 667401840 is about 873.9014633015.

The spelling of 667401840 in words is "six hundred sixty-seven million, four hundred one thousand, eight hundred forty".