66921123 has 16 divisors (see below), whose sum is σ = 91963040. Its totient is φ = 43255296.

The previous prime is 66921103. The next prime is 66921131. The reversal of 66921123 is 32112966.

It is not a de Polignac number, because 66921123 - 2¹⁰ = 66920099 is a prime.

It is a super-2 number, since 2×66921123² = 8956873407162258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66921103) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36513 + ... + 38301.

It is an arithmetic number, because the mean of its divisors is an integer number (5747690).

Almost surely, 2^66921123 is an apocalyptic number.

66921123 is a deficient number, since it is larger than the sum of its proper divisors (25041917).

66921123 is a wasteful number, since it uses less digits than its factorization.

66921123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2166.

The product of its digits is 3888, while the sum is 30.

The square root of 66921123 is about 8180.5331733329. The cubic root of 66921123 is about 405.9953630150.

The spelling of 66921123 in words is "sixty-six million, nine hundred twenty-one thousand, one hundred twenty-three".