66554623 has 4 divisors (see below), whose sum is σ = 68849640. Its totient is φ = 64259608.

The previous prime is 66554597. The next prime is 66554633. The reversal of 66554623 is 32645566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32645566 = 2 ⋅16322783.

It is a cyclic number.

It is not a de Polignac number, because 66554623 - 2¹⁷ = 66423551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66554633) 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, 1147465 + ... + 1147522.

It is an arithmetic number, because the mean of its divisors is an integer number (17212410).

Almost surely, 2^66554623 is an apocalyptic number.

66554623 is a deficient number, since it is larger than the sum of its proper divisors (2295017).

66554623 is a wasteful number, since it uses less digits than its factorization.

66554623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2295016.

The product of its digits is 129600, while the sum is 37.

The square root of 66554623 is about 8158.1016786995. The cubic root of 66554623 is about 405.2528482572.

The spelling of 66554623 in words is "sixty-six million, five hundred fifty-four thousand, six hundred twenty-three".