66119021 has 4 divisors (see below), whose sum is σ = 66214044. Its totient is φ = 66024000.

The previous prime is 66118991. The next prime is 66119029. The reversal of 66119021 is 12091166.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12091166 = 2 ⋅6045583.

It can be written as a sum of positive squares in 2 ways, for example, as 60062500 + 6056521 = 7750^2 + 2461^2 .

It is a cyclic number.

It is not a de Polignac number, because 66119021 - 2⁶ = 66118957 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 (66119029) 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, 46460 + ... + 47861.

It is an arithmetic number, because the mean of its divisors is an integer number (16553511).

Almost surely, 2^66119021 is an apocalyptic number.

It is an amenable number.

66119021 is a deficient number, since it is larger than the sum of its proper divisors (95023).

66119021 is an equidigital number, since it uses as much as digits as its factorization.

66119021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95022.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 66119021 is about 8131.3603412959. The cubic root of 66119021 is about 404.3667816509.

The spelling of 66119021 in words is "sixty-six million, one hundred nineteen thousand, twenty-one".