3666195421 has 4 divisors (see below), whose sum is σ = 4189937632. Its totient is φ = 3142453212.

The previous prime is 3666195409. The next prime is 3666195433. The reversal of 3666195421 is 1245916663.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1245916663 = 79 ⋅15771097.

It is an interprime number because it is at equal distance from previous prime (3666195409) and next prime (3666195433).

It is a cyclic number.

It is not a de Polignac number, because 3666195421 - 2¹⁵ = 3666162653 is a prime.

It is a super-2 number, since 2×3666195421² = 26881977729922734482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3666195451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 261871095 + ... + 261871108.

It is an arithmetic number, because the mean of its divisors is an integer number (1047484408).

Almost surely, 2^3666195421 is an apocalyptic number.

It is an amenable number.

3666195421 is a deficient number, since it is larger than the sum of its proper divisors (523742211).

3666195421 is an equidigital number, since it uses as much as digits as its factorization.

3666195421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523742210.

The product of its digits is 233280, while the sum is 43.

The square root of 3666195421 is about 60549.1157738905. The cubic root of 3666195421 is about 1541.9556058946.

The spelling of 3666195421 in words is "three billion, six hundred sixty-six million, one hundred ninety-five thousand, four hundred twenty-one".