667017987720 has 512 divisors, whose sum is σ = 2437585920000. Its totient is φ = 142628511744.

The previous prime is 667017987607. The next prime is 667017987733. The reversal of 667017987720 is 27789710766.

667017987720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 795015061 + ... + 795015899.

It is an arithmetic number, because the mean of its divisors is an integer number (4760910000).

Almost surely, 2^667017987720 is an apocalyptic number.

667017987720 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 667017987720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1218792960000).

667017987720 is an abundant number, since it is smaller than the sum of its proper divisors (1770567932280).

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

667017987720 is a wasteful number, since it uses less digits than its factorization.

667017987720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1445 (or 1441 counting only the distinct ones).

The product of its (nonzero) digits is 12446784, while the sum is 60.

The spelling of 667017987720 in words is "six hundred sixty-seven billion, seventeen million, nine hundred eighty-seven thousand, seven hundred twenty".