68646620025 has 27 divisors (see below), whose sum is σ = 122960763471. Its totient is φ = 36609434640.

The previous prime is 68646620011. The next prime is 68646620033. The reversal of 68646620025 is 52002664686.

The square root of 68646620025 is 262005.

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

It can be written as a sum of positive squares in only one way, i.e., 24712783209 + 43933836816 = 157203^2 + 209604^2 .

It is a de Polignac number, because none of the positive numbers 2^k-68646620025 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 3921342 + ... + 3938808.

Almost surely, 2^68646620025 is an apocalyptic number.

68646620025 is the 262005-th square number.

68646620025 is the 131003-rd centered octagonal number.

It is an amenable number.

68646620025 is a deficient number, since it is larger than the sum of its proper divisors (54314143446).

68646620025 is an frugal number, since it uses more digits than its factorization.

68646620025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34950 (or 17475 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 45.

The spelling of 68646620025 in words is "sixty-eight billion, six hundred forty-six million, six hundred twenty thousand, twenty-five".