68002557529 has 3 divisors (see below), whose sum is σ = 68002818303. Its totient is φ = 68002296756.

The previous prime is 68002557517. The next prime is 68002557577. The reversal of 68002557529 is 92575520086.

It is a happy number.

The square root of 68002557529 is 260773.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 55335505225 + 12667052304 = 235235^2 + 112548^2 .

It is not a de Polignac number, because 68002557529 - 2⁹ = 68002557017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68002557629) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 130387 + ... + 391159.

It is an arithmetic number, because the mean of its divisors is an integer number (22667606101).

Almost surely, 2^68002557529 is an apocalyptic number.

68002557529 is the 260773-rd square number.

68002557529 is the 130387-th centered octagonal number.

It is an amenable number.

68002557529 is a deficient number, since it is larger than the sum of its proper divisors (260774).

68002557529 is an frugal number, since it uses more digits than its factorization.

68002557529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521546 (or 260773 counting only the distinct ones).

The product of its (nonzero) digits is 1512000, while the sum is 49.

Multiplying 68002557529 by its sum of digits (49), we get a square (3332125318921 = 1825411²).

The spelling of 68002557529 in words is "sixty-eight billion, two million, five hundred fifty-seven thousand, five hundred twenty-nine".