7618561 has 4 divisors (see below), whose sum is σ = 7881300. Its totient is φ = 7355824.

The previous prime is 7618549. The next prime is 7618607. The reversal of 7618561 is 1658167.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1658167 = 7 ⋅236881.

It can be written as a sum of positive squares in 2 ways, for example, as 4080400 + 3538161 = 2020^2 + 1881^2 .

It is a cyclic number.

It is not a de Polignac number, because 7618561 - 2¹¹ = 7616513 is a prime.

It is a super-3 number, since 3×7618561³ (a number of 22 digits) contains 333 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7618861) 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, 131326 + ... + 131383.

It is an arithmetic number, because the mean of its divisors is an integer number (1970325).

It is a Proth number, since it is equal to 465 ⋅ 2¹⁴ + 1 and 465 < 2¹⁴.

Almost surely, 2^7618561 is an apocalyptic number.

It is an amenable number.

7618561 is a deficient number, since it is larger than the sum of its proper divisors (262739).

7618561 is a wasteful number, since it uses less digits than its factorization.

7618561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262738.

The product of its digits is 10080, while the sum is 34.

The square root of 7618561 is about 2760.1740887125. The cubic root of 7618561 is about 196.7694400435.

The spelling of 7618561 in words is "seven million, six hundred eighteen thousand, five hundred sixty-one".