7890661 has 2 divisors, whose sum is σ = 7890662. Its totient is φ = 7890660.

The previous prime is 7890611. The next prime is 7890683. The reversal of 7890661 is 1660987.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5428900 + 2461761 = 2330^2 + 1569^2 .

It is a cyclic number.

It is not a de Polignac number, because 7890661 - 2¹¹ = 7888613 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 7890661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7890611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3945330 + 3945331.

It is an arithmetic number, because the mean of its divisors is an integer number (3945331).

Almost surely, 2^7890661 is an apocalyptic number.

It is an amenable number.

7890661 is a deficient number, since it is larger than the sum of its proper divisors (1).

7890661 is an equidigital number, since it uses as much as digits as its factorization.

7890661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 7890661 is about 2809.0320396891. The cubic root of 7890661 is about 199.0846588102.

The spelling of 7890661 in words is "seven million, eight hundred ninety thousand, six hundred sixty-one".