9078071221 has 4 divisors (see below), whose sum is σ = 9094369932. Its totient is φ = 9061772512.

The previous prime is 9078071159. The next prime is 9078071269. The reversal of 9078071221 is 1221708709.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1221708709 = 13 ⋅93977593.

It can be written as a sum of positive squares in 2 ways, for example, as 5823368721 + 3254702500 = 76311^2 + 57050^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9078071221 is a prime.

It is a super-2 number, since 2×9078071221² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9078071021) 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, 8148520 + ... + 8149633.

It is an arithmetic number, because the mean of its divisors is an integer number (2273592483).

Almost surely, 2^9078071221 is an apocalyptic number.

It is an amenable number.

9078071221 is a deficient number, since it is larger than the sum of its proper divisors (16298711).

9078071221 is a wasteful number, since it uses less digits than its factorization.

9078071221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16298710.

The product of its (nonzero) digits is 14112, while the sum is 37.

The square root of 9078071221 is about 95278.9127824200. The cubic root of 9078071221 is about 2086.0811328752.

The spelling of 9078071221 in words is "nine billion, seventy-eight million, seventy-one thousand, two hundred twenty-one".