958216561 has 4 divisors (see below), whose sum is σ = 958282612. Its totient is φ = 958150512.

The previous prime is 958216559. The next prime is 958216573. The reversal of 958216561 is 165612859.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 446054400 + 512162161 = 21120^2 + 22631^2 .

It is a cyclic number.

It is not a de Polignac number, because 958216561 - 2¹ = 958216559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (958216591) 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, 750 + ... + 43783.

It is an arithmetic number, because the mean of its divisors is an integer number (239570653).

Almost surely, 2^958216561 is an apocalyptic number.

It is an amenable number.

958216561 is a deficient number, since it is larger than the sum of its proper divisors (66051).

958216561 is a wasteful number, since it uses less digits than its factorization.

958216561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66050.

The product of its digits is 129600, while the sum is 43.

The square root of 958216561 is about 30955.0732675599. The cubic root of 958216561 is about 985.8735706655.

The spelling of 958216561 in words is "nine hundred fifty-eight million, two hundred sixteen thousand, five hundred sixty-one".