4355161621 has 4 divisors (see below), whose sum is σ = 4355851372. Its totient is φ = 4354471872.

The previous prime is 4355161579. The next prime is 4355161651. The reversal of 4355161621 is 1261615534.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1261615534 = 2 ⋅630807767.

It can be written as a sum of positive squares in 2 ways, for example, as 2468996721 + 1886164900 = 49689^2 + 43430^2 .

It is a cyclic number.

It is not a de Polignac number, because 4355161621 - 2⁷ = 4355161493 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 (4355161651) 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, 335316 + ... + 348061.

It is an arithmetic number, because the mean of its divisors is an integer number (1088962843).

Almost surely, 2^4355161621 is an apocalyptic number.

It is an amenable number.

4355161621 is a deficient number, since it is larger than the sum of its proper divisors (689751).

4355161621 is an equidigital number, since it uses as much as digits as its factorization.

4355161621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689750.

The product of its digits is 21600, while the sum is 34.

The square root of 4355161621 is about 65993.6483383060. The cubic root of 4355161621 is about 1633.0573080089.

The spelling of 4355161621 in words is "four billion, three hundred fifty-five million, one hundred sixty-one thousand, six hundred twenty-one".