65615555 has 4 divisors (see below), whose sum is σ = 78738672. Its totient is φ = 52492440.

The previous prime is 65615551. The next prime is 65615581. The reversal of 65615555 is 55551656.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 65615555 - 2² = 65615551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65615551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6561551 + ... + 6561560.

It is an arithmetic number, because the mean of its divisors is an integer number (19684668).

Almost surely, 2^65615555 is an apocalyptic number.

65615555 is a deficient number, since it is larger than the sum of its proper divisors (13123117).

65615555 is a wasteful number, since it uses less digits than its factorization.

65615555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13123116.

The product of its digits is 112500, while the sum is 38.

The square root of 65615555 is about 8100.3428939768. The cubic root of 65615555 is about 403.3378096779.

The spelling of 65615555 in words is "sixty-five million, six hundred fifteen thousand, five hundred fifty-five".