68640225 has 12 divisors (see below), whose sum is σ = 113485296. Its totient is φ = 36608080.

The previous prime is 68640193. The next prime is 68640233. The reversal of 68640225 is 52204686.

It is not a de Polignac number, because 68640225 - 2⁵ = 68640193 is a prime.

It is a super-2 number, since 2×68640225² = 9422960976101250, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 457527 + ... + 457676.

It is an arithmetic number, because the mean of its divisors is an integer number (9457108).

Almost surely, 2^68640225 is an apocalyptic number.

It is an amenable number.

68640225 is a deficient number, since it is larger than the sum of its proper divisors (44845071).

68640225 is a wasteful number, since it uses less digits than its factorization.

68640225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 915216 (or 915211 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 33.

The square root of 68640225 is about 8284.9396497500. The cubic root of 68640225 is about 409.4424803781.

The spelling of 68640225 in words is "sixty-eight million, six hundred forty thousand, two hundred twenty-five".