65561550 has 24 divisors (see below), whose sum is σ = 162593016. Its totient is φ = 17483040.

The previous prime is 65561543. The next prime is 65561563. The reversal of 65561550 is 5516556.

It is a congruent number.

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, 218389 + ... + 218688.

It is an arithmetic number, because the mean of its divisors is an integer number (6774709).

Almost surely, 2^65561550 is an apocalyptic number.

65561550 is an abundant number, since it is smaller than the sum of its proper divisors (97031466).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65561550 is a wasteful number, since it uses less digits than its factorization.

65561550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437092 (or 437087 counting only the distinct ones).

The product of its (nonzero) digits is 22500, while the sum is 33.

The square root of 65561550 is about 8097.0087069238. The cubic root of 65561550 is about 403.2271233368.

The spelling of 65561550 in words is "sixty-five million, five hundred sixty-one thousand, five hundred fifty".