664798532501 has 2 divisors, whose sum is σ = 664798532502. Its totient is φ = 664798532500.

The previous prime is 664798532413. The next prime is 664798532507. The reversal of 664798532501 is 105235897466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 523235222500 + 141563310001 = 723350^2 + 376249^2 .

It is a cyclic number.

It is not a de Polignac number, because 664798532501 - 2²⁶ = 664731423637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664798532507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332399266250 + 332399266251.

It is an arithmetic number, because the mean of its divisors is an integer number (332399266251).

It is a 1-persistent number, because it is pandigital, but 2⋅664798532501 = 1329597065002 is not.

Almost surely, 2^664798532501 is an apocalyptic number.

It is an amenable number.

664798532501 is a deficient number, since it is larger than the sum of its proper divisors (1).

664798532501 is an equidigital number, since it uses as much as digits as its factorization.

664798532501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10886400, while the sum is 56.

The spelling of 664798532501 in words is "six hundred sixty-four billion, seven hundred ninety-eight million, five hundred thirty-two thousand, five hundred one".