3619650721 has 4 divisors (see below), whose sum is σ = 3625298244. Its totient is φ = 3614003200.

The previous prime is 3619650719. The next prime is 3619650733. The reversal of 3619650721 is 1270569163.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2610699025 + 1008951696 = 51095^2 + 31764^2 .

It is a cyclic number.

It is not a de Polignac number, because 3619650721 - 2¹ = 3619650719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3619150721) 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, 2822800 + ... + 2824081.

It is an arithmetic number, because the mean of its divisors is an integer number (906324561).

Almost surely, 2^3619650721 is an apocalyptic number.

It is an amenable number.

3619650721 is a deficient number, since it is larger than the sum of its proper divisors (5647523).

3619650721 is an equidigital number, since it uses as much as digits as its factorization.

3619650721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5647522.

The product of its (nonzero) digits is 68040, while the sum is 40.

The square root of 3619650721 is about 60163.5331492425. The cubic root of 3619650721 is about 1535.4024233934.

The spelling of 3619650721 in words is "three billion, six hundred nineteen million, six hundred fifty thousand, seven hundred twenty-one".