664755557466 has 512 divisors, whose sum is σ = 1937317036032. Its totient is φ = 146451317760.

The previous prime is 664755557399. The next prime is 664755557497.

664755557466 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a junction number, because it is equal to n+sod(n) for n = 664755557397 and 664755557406.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 424221015 + ... + 424222581.

It is an arithmetic number, because the mean of its divisors is an integer number (3783822336).

Almost surely, 2^664755557466 is an apocalyptic number.

664755557466 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 664755557466, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (968658518016).

664755557466 is an abundant number, since it is smaller than the sum of its proper divisors (1272561478566).

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

664755557466 is a wasteful number, since it uses less digits than its factorization.

664755557466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1746.

The product of its digits is 635040000, while the sum is 66.

It can be divided in two parts, 664755 and 557466, that added together give a palindrome (1222221).

The spelling of 664755557466 in words is "six hundred sixty-four billion, seven hundred fifty-five million, five hundred fifty-seven thousand, four hundred sixty-six".