4621605721 has 4 divisors (see below), whose sum is σ = 4622965632. Its totient is φ = 4620245812.

The previous prime is 4621605689. The next prime is 4621605743. The reversal of 4621605721 is 1275061264.

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.

It is a cyclic number.

It is not a de Polignac number, because 4621605721 - 2⁵ = 4621605689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4621605761) 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, 674845 + ... + 681658.

It is an arithmetic number, because the mean of its divisors is an integer number (1155741408).

Almost surely, 2^4621605721 is an apocalyptic number.

It is an amenable number.

4621605721 is a deficient number, since it is larger than the sum of its proper divisors (1359911).

4621605721 is a wasteful number, since it uses less digits than its factorization.

4621605721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1359910.

The product of its (nonzero) digits is 20160, while the sum is 34.

The square root of 4621605721 is about 67982.3927278233. The cubic root of 4621605721 is about 1665.7032408248.

Adding to 4621605721 its reverse (1275061264), we get a palindrome (5896666985).

The spelling of 4621605721 in words is "four billion, six hundred twenty-one million, six hundred five thousand, seven hundred twenty-one".