7827661 has 2 divisors, whose sum is σ = 7827662. Its totient is φ = 7827660.

The previous prime is 7827637. The next prime is 7827671. The reversal of 7827661 is 1667287.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7257636 + 570025 = 2694^2 + 755^2 .

It is an emirp because it is prime and its reverse (1667287) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7827661 - 2²¹ = 5730509 is a prime.

It is a super-2 number, since 2×7827661² = 122544553461842, which contains 22 as substring.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 7827661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7827671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3913830 + 3913831.

It is an arithmetic number, because the mean of its divisors is an integer number (3913831).

Almost surely, 2^7827661 is an apocalyptic number.

It is an amenable number.

7827661 is a deficient number, since it is larger than the sum of its proper divisors (1).

7827661 is an equidigital number, since it uses as much as digits as its factorization.

7827661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 28224, while the sum is 37.

The square root of 7827661 is about 2797.7957395064. The cubic root of 7827661 is about 198.5534036890.

The spelling of 7827661 in words is "seven million, eight hundred twenty-seven thousand, six hundred sixty-one".