66621224 has 32 divisors (see below), whose sum is σ = 127033920. Its totient is φ = 32750976.

The previous prime is 66621221. The next prime is 66621227. The reversal of 66621224 is 42212666.

It is an interprime number because it is at equal distance from previous prime (66621221) and next prime (66621227).

It is not an unprimeable number, because it can be changed into a prime (66621221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 191819 + ... + 192165.

It is an arithmetic number, because the mean of its divisors is an integer number (3969810).

Almost surely, 2^66621224 is an apocalyptic number.

It is an amenable number.

66621224 is a deficient number, since it is larger than the sum of its proper divisors (60412696).

66621224 is a wasteful number, since it uses less digits than its factorization.

66621224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689 (or 685 counting only the distinct ones).

The product of its digits is 6912, while the sum is 29.

The square root of 66621224 is about 8162.1825512543. The cubic root of 66621224 is about 405.3879816044.

The spelling of 66621224 in words is "sixty-six million, six hundred twenty-one thousand, two hundred twenty-four".