51665655 has 16 divisors (see below), whose sum is σ = 87016320. Its totient is φ = 26104608.

The previous prime is 51665609. The next prime is 51665687. The reversal of 51665655 is 55656615.

It is not a de Polignac number, because 51665655 - 2⁸ = 51665399 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 90357 + ... + 90926.

It is an arithmetic number, because the mean of its divisors is an integer number (5438520).

Almost surely, 2^51665655 is an apocalyptic number.

51665655 is a deficient number, since it is larger than the sum of its proper divisors (35350665).

51665655 is a wasteful number, since it uses less digits than its factorization.

51665655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181310.

The product of its digits is 135000, while the sum is 39.

The square root of 51665655 is about 7187.8825115607. The cubic root of 51665655 is about 372.4494293464.

The spelling of 51665655 in words is "fifty-one million, six hundred sixty-five thousand, six hundred fifty-five".