2606664421 has 4 divisors (see below), whose sum is σ = 2670241644. Its totient is φ = 2543087200.

The previous prime is 2606664377. The next prime is 2606664443. The reversal of 2606664421 is 1244666062.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1244666062 = 2 ⋅622333031.

It can be written as a sum of positive squares in 2 ways, for example, as 406022500 + 2200641921 = 20150^2 + 46911^2 .

It is a cyclic number.

It is not a de Polignac number, because 2606664421 - 2⁷ = 2606664293 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 (2606664461) 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, 31788550 + ... + 31788631.

It is an arithmetic number, because the mean of its divisors is an integer number (667560411).

Almost surely, 2^2606664421 is an apocalyptic number.

It is an amenable number.

2606664421 is a deficient number, since it is larger than the sum of its proper divisors (63577223).

2606664421 is an equidigital number, since it uses as much as digits as its factorization.

2606664421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63577222.

The product of its (nonzero) digits is 82944, while the sum is 37.

The square root of 2606664421 is about 51055.5033370547. The cubic root of 2606664421 is about 1376.2427413168.

The spelling of 2606664421 in words is "two billion, six hundred six million, six hundred sixty-four thousand, four hundred twenty-one".