66621610 has 32 divisors (see below), whose sum is σ = 132414912. Its totient is φ = 23930880.

The previous prime is 66621587. The next prime is 66621617. The reversal of 66621610 is 1612666.

66621610 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (66621617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5482 + ... + 12778.

It is an arithmetic number, because the mean of its divisors is an integer number (4137966).

Almost surely, 2^66621610 is an apocalyptic number.

66621610 is a deficient number, since it is larger than the sum of its proper divisors (65793302).

66621610 is a wasteful number, since it uses less digits than its factorization.

66621610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7398.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 66621610 is about 8162.2061968563. The cubic root of 66621610 is about 405.3887645354.

The spelling of 66621610 in words is "sixty-six million, six hundred twenty-one thousand, six hundred ten".