68988699649 has 3 divisors (see below), whose sum is σ = 68988962307. Its totient is φ = 68988436992.

The previous prime is 68988699623. The next prime is 68988699679. The reversal of 68988699649 is 94699688986.

The square root of 68988699649 is 262657.

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

68988699649 is nontrivially palindromic in base 8.

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., 52612890625 + 16375809024 = 229375^2 + 127968^2 .

It is not a de Polignac number, because 68988699649 - 2¹⁵ = 68988666881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68988699679) 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, 131329 + ... + 393985.

It is an arithmetic number, because the mean of its divisors is an integer number (22996320769).

Almost surely, 2^68988699649 is an apocalyptic number.

68988699649 is the 262657-th square number.

68988699649 is the 131329-th centered octagonal number.

It is an amenable number.

68988699649 is a deficient number, since it is larger than the sum of its proper divisors (262658).

68988699649 is an frugal number, since it uses more digits than its factorization.

68988699649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 525314 (or 262657 counting only the distinct ones).

The product of its digits is 2902376448, while the sum is 82.

The spelling of 68988699649 in words is "sixty-eight billion, nine hundred eighty-eight million, six hundred ninety-nine thousand, six hundred forty-nine".